diff --git a/.editorconfig b/.editorconfig
index bb0c3a50..b7f043d6 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -14,6 +14,10 @@ dotnet_diagnostic.CA1034.severity = none
 dotnet_diagnostic.CA1054.severity = none
 dotnet_diagnostic.CA2227.severity = none
 dotnet_diagnostic.CA1308.severity = none
+dotnet_diagnostic.CA1002.severity = none
+# TODO: Enable for next major version, EventArgs breaking change:
+dotnet_diagnostic.CA1003.severity = none
+#
 # Sort using and Import directives with System.* appearing first
 dotnet_sort_system_directives_first = true
 dotnet_style_require_accessibility_modifiers = always:warning
diff --git a/SpotifyAPI.Web.Auth/AssemblyInfo.cs b/SpotifyAPI.Web.Auth/AssemblyInfo.cs
new file mode 100644
index 00000000..661cd812
--- /dev/null
+++ b/SpotifyAPI.Web.Auth/AssemblyInfo.cs
@@ -0,0 +1,5 @@
+using System;
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("SpotifyAPI.Web.Tests")]
+[assembly: CLSCompliant(true)]
diff --git a/SpotifyAPI.Web.Tests/Http/NetHTTPClientTest.cs b/SpotifyAPI.Web.Tests/Http/NetHTTPClientTest.cs
deleted file mode 100644
index f93948cf..00000000
--- a/SpotifyAPI.Web.Tests/Http/NetHTTPClientTest.cs
+++ /dev/null
@@ -1,20 +0,0 @@
-using System.Collections.Generic;
-using System;
-using System.Threading.Tasks;
-using NUnit.Framework;
-
-namespace SpotifyAPI.Web.Tests
-{
-  [TestFixture]
-  public class NetHTTPClientTest
-  {
-    [TestFixture]
-    public class BuildRequestsMethod
-    {
-      public void AddsHeaders()
-      {
-
-      }
-    }
-  }
-}
diff --git a/SpotifyAPI.Web.Tests/UtilTests/URIExtensionTest.cs b/SpotifyAPI.Web.Tests/UtilTests/URIExtensionTest.cs
index 96daa508..6b3d7a2d 100644
--- a/SpotifyAPI.Web.Tests/UtilTests/URIExtensionTest.cs
+++ b/SpotifyAPI.Web.Tests/UtilTests/URIExtensionTest.cs
@@ -11,7 +11,7 @@ namespace SpotifyAPI.Web.Tests
     public void ApplyParameters_WithoutExistingParameters()
     {
       var expected = "http://google.com/?hello=world&nice=day";
-      Uri uri = new Uri("http://google.com/");
+      var uri = new Uri("http://google.com/");
 
       var parameters = new Dictionary<string, string>
       {
@@ -25,7 +25,7 @@ namespace SpotifyAPI.Web.Tests
     public void ApplyParameters_WithExistingParameters()
     {
       var expected = "http://google.com/?existing=paramter&hello=world&nice=day";
-      Uri uri = new Uri("http://google.com/?existing=paramter");
+      var uri = new Uri("http://google.com/?existing=paramter");
 
       var parameters = new Dictionary<string, string>
       {
@@ -39,7 +39,7 @@ namespace SpotifyAPI.Web.Tests
     public void ApplyParameters_HandlesEscape()
     {
       var expected = "http://google.com/?existing=paramter&hello=%26world++";
-      Uri uri = new Uri("http://google.com/?existing=paramter");
+      var uri = new Uri("http://google.com/?existing=paramter");
 
       var parameters = new Dictionary<string, string>
       {
diff --git a/SpotifyAPI.Web/Assembly.cs b/SpotifyAPI.Web/Assembly.cs
index 6e71e55c..661cd812 100644
--- a/SpotifyAPI.Web/Assembly.cs
+++ b/SpotifyAPI.Web/Assembly.cs
@@ -1,3 +1,5 @@
+using System;
 using System.Runtime.CompilerServices;
 
 [assembly: InternalsVisibleTo("SpotifyAPI.Web.Tests")]
+[assembly: CLSCompliant(true)]
diff --git a/SpotifyAPI.Web/Clients/APIClient.cs b/SpotifyAPI.Web/Clients/APIClient.cs
index a778e1ae..c12c983f 100644
--- a/SpotifyAPI.Web/Clients/APIClient.cs
+++ b/SpotifyAPI.Web/Clients/APIClient.cs
@@ -4,7 +4,7 @@ namespace SpotifyAPI.Web
 {
   public abstract class APIClient
   {
-    public APIClient(IAPIConnector apiConnector)
+    protected APIClient(IAPIConnector apiConnector)
     {
       Ensure.ArgumentNotNull(apiConnector, nameof(apiConnector));
 
diff --git a/SpotifyAPI.Web/Clients/PlaylistsClient.cs b/SpotifyAPI.Web/Clients/PlaylistsClient.cs
index 3b3ab3e5..6a598d00 100644
--- a/SpotifyAPI.Web/Clients/PlaylistsClient.cs
+++ b/SpotifyAPI.Web/Clients/PlaylistsClient.cs
@@ -49,12 +49,12 @@ namespace SpotifyAPI.Web
       return API.Post<FullPlaylist>(URLs.UserPlaylists(userId), null, request.BuildBodyParams());
     }
 
-    public async Task<bool> UploadCover(string playlistId, string base64Jpg)
+    public async Task<bool> UploadCover(string playlistId, string base64JpgData)
     {
       Ensure.ArgumentNotNullOrEmptyString(playlistId, nameof(playlistId));
-      Ensure.ArgumentNotNullOrEmptyString(base64Jpg, nameof(base64Jpg));
+      Ensure.ArgumentNotNullOrEmptyString(base64JpgData, nameof(base64JpgData));
 
-      var statusCode = await API.PutRaw(URLs.PlaylistImages(playlistId), null, base64Jpg).ConfigureAwait(false);
+      var statusCode = await API.PutRaw(URLs.PlaylistImages(playlistId), null, base64JpgData).ConfigureAwait(false);
       return statusCode == HttpStatusCode.Accepted;
     }
 
diff --git a/SpotifyAPI.Web/Clients/SpotifyClient.cs b/SpotifyAPI.Web/Clients/SpotifyClient.cs
index 31bcad71..f4266540 100644
--- a/SpotifyAPI.Web/Clients/SpotifyClient.cs
+++ b/SpotifyAPI.Web/Clients/SpotifyClient.cs
@@ -24,7 +24,9 @@ namespace SpotifyAPI.Web
       Ensure.ArgumentNotNull(config, nameof(config));
       if (config.Authenticator == null)
       {
-        throw new NullReferenceException("Authenticator in config is null. Please supply it via `WithAuthenticator` or `WithToken`");
+#pragma warning disable CA2208
+        throw new ArgumentNullException("Authenticator in config is null. Please supply it via `WithAuthenticator` or `WithToken`");
+#pragma warning restore CA2208
       }
 
       _apiConnector = new APIConnector(
diff --git a/SpotifyAPI.Web/Http/APIConnector.cs b/SpotifyAPI.Web/Http/APIConnector.cs
index ecc24862..21961811 100644
--- a/SpotifyAPI.Web/Http/APIConnector.cs
+++ b/SpotifyAPI.Web/Http/APIConnector.cs
@@ -279,15 +279,13 @@ namespace SpotifyAPI.Web.Http
         return;
       }
 
-      switch (response.StatusCode)
+      throw response.StatusCode switch
       {
-        case HttpStatusCode.Unauthorized:
-          throw new APIUnauthorizedException(response);
-        case (HttpStatusCode)429: // TODO: Remove hack once .netstandard 2.0 is not supported
-          throw new APITooManyRequestsException(response);
-        default:
-          throw new APIException(response);
-      }
+        HttpStatusCode.Unauthorized => new APIUnauthorizedException(response),
+        // TODO: Remove hack once .netstandard 2.0 is not supported
+        (HttpStatusCode)429 => new APITooManyRequestsException(response),
+        _ => new APIException(response),
+      };
     }
   }
 }
diff --git a/SpotifyAPI.Web/Http/NetHttpClient.cs b/SpotifyAPI.Web/Http/NetHttpClient.cs
index 26b4435b..5a8a72c0 100644
--- a/SpotifyAPI.Web/Http/NetHttpClient.cs
+++ b/SpotifyAPI.Web/Http/NetHttpClient.cs
@@ -35,14 +35,12 @@ namespace SpotifyAPI.Web.Http
     {
       Ensure.ArgumentNotNull(request, nameof(request));
 
-      using (HttpRequestMessage requestMsg = BuildRequestMessage(request))
-      {
-        var responseMsg = await _httpClient
-                .SendAsync(requestMsg, HttpCompletionOption.ResponseContentRead)
-                .ConfigureAwait(false);
+      using HttpRequestMessage requestMsg = BuildRequestMessage(request);
+      var responseMsg = await _httpClient
+              .SendAsync(requestMsg, HttpCompletionOption.ResponseContentRead)
+              .ConfigureAwait(false);
 
-        return await BuildResponse(responseMsg).ConfigureAwait(false);
-      }
+      return await BuildResponse(responseMsg).ConfigureAwait(false);
     }
 
     private static async Task<IResponse> BuildResponse(HttpResponseMessage responseMsg)
@@ -50,19 +48,17 @@ namespace SpotifyAPI.Web.Http
       Ensure.ArgumentNotNull(responseMsg, nameof(responseMsg));
 
       // We only support text stuff for now
-      using (var content = responseMsg.Content)
-      {
-        var headers = responseMsg.Headers.ToDictionary(header => header.Key, header => header.Value.First());
-        var body = await responseMsg.Content.ReadAsStringAsync().ConfigureAwait(false);
-        var contentType = content.Headers?.ContentType?.MediaType;
+      using var content = responseMsg.Content;
+      var headers = responseMsg.Headers.ToDictionary(header => header.Key, header => header.Value.First());
+      var body = await responseMsg.Content.ReadAsStringAsync().ConfigureAwait(false);
+      var contentType = content.Headers?.ContentType?.MediaType;
 
-        return new Response(headers)
-        {
-          ContentType = contentType,
-          StatusCode = responseMsg.StatusCode,
-          Body = body
-        };
-      }
+      return new Response(headers)
+      {
+        ContentType = contentType,
+        StatusCode = responseMsg.StatusCode,
+        Body = body
+      };
     }
 
     private static HttpRequestMessage BuildRequestMessage(IRequest request)
diff --git a/SpotifyAPI.Web/Http/SimpleConsoleHTTPLogger.cs b/SpotifyAPI.Web/Http/SimpleConsoleHTTPLogger.cs
index 9fb3e0ae..6049e17e 100644
--- a/SpotifyAPI.Web/Http/SimpleConsoleHTTPLogger.cs
+++ b/SpotifyAPI.Web/Http/SimpleConsoleHTTPLogger.cs
@@ -16,7 +16,7 @@ namespace SpotifyAPI.Web.Http
       if (request.Parameters != null)
       {
         parameters = string.Join(",",
-          request.Parameters?.Select(kv => kv.Key + "=" + kv.Value)?.ToArray() ?? Array.Empty<string>()
+          request.Parameters.Select(kv => kv.Key + "=" + kv.Value)?.ToArray() ?? Array.Empty<string>()
         );
       }
 
@@ -33,7 +33,7 @@ namespace SpotifyAPI.Web.Http
       string? body = response.Body?.ToString()?.Replace("\n", "", StringComparison.InvariantCulture);
 #endif
 
-      body = body?.Substring(0, Math.Min(50, body?.Length ?? 0));
+      body = body?.Substring(0, Math.Min(50, body.Length));
       Console.WriteLine("--> {0} {1} {2}\n", response.StatusCode, response.ContentType, body);
     }
   }
diff --git a/SpotifyAPI.Web/Models/Converters/PlayableItemConverter.cs b/SpotifyAPI.Web/Models/Converters/PlayableItemConverter.cs
index 74a7aa48..bb5d5ef1 100644
--- a/SpotifyAPI.Web/Models/Converters/PlayableItemConverter.cs
+++ b/SpotifyAPI.Web/Models/Converters/PlayableItemConverter.cs
@@ -36,7 +36,7 @@ namespace SpotifyAPI.Web
       }
       else
       {
-        throw new Exception($@"Received unkown playlist element type: {type}.
+        throw new APIException($@"Received unkown playlist element type: {type}.
 If you're requesting a subset of available fields via the fields query paramter,
 make sure to include at least the type field. Often it's `items(track(type))` or `item(type)`");
       }
diff --git a/SpotifyAPI.Web/Models/Request/LoginRequest.cs b/SpotifyAPI.Web/Models/Request/LoginRequest.cs
index 32944d61..40a9fa90 100644
--- a/SpotifyAPI.Web/Models/Request/LoginRequest.cs
+++ b/SpotifyAPI.Web/Models/Request/LoginRequest.cs
@@ -29,7 +29,7 @@ namespace SpotifyAPI.Web
 
     public Uri ToUri()
     {
-      StringBuilder builder = new StringBuilder(SpotifyUrls.Authorize.ToString());
+      var builder = new StringBuilder(SpotifyUrls.Authorize.ToString());
       builder.Append($"?client_id={ClientId}");
       builder.Append($"&response_type={ResponseTypeParam.ToString().ToLower(CultureInfo.InvariantCulture)}");
       builder.Append($"&redirect_uri={HttpUtility.UrlEncode(RedirectUri.ToString())}");
diff --git a/SpotifyAPI.Web/Models/Request/RequestParams.cs b/SpotifyAPI.Web/Models/Request/RequestParams.cs
index 97a05bd7..40066325 100644
--- a/SpotifyAPI.Web/Models/Request/RequestParams.cs
+++ b/SpotifyAPI.Web/Models/Request/RequestParams.cs
@@ -11,7 +11,7 @@ namespace SpotifyAPI.Web
   public abstract class RequestParams
   {
     private static readonly ConcurrentDictionary<Type, List<(PropertyInfo, BodyParamAttribute)>> _bodyParamsCache =
-      new ConcurrentDictionary<Type, List<(PropertyInfo, BodyParamAttribute)>>();
+      new();
 
     public JObject BuildBodyParams()
     {
@@ -59,7 +59,7 @@ namespace SpotifyAPI.Web
     }
 
     private static readonly ConcurrentDictionary<Type, List<(PropertyInfo, QueryParamAttribute)>> _queryParamsCache =
-      new ConcurrentDictionary<Type, List<(PropertyInfo, QueryParamAttribute)>>();
+      new();
 
     public Dictionary<string, string> BuildQueryParams()
     {
@@ -146,7 +146,7 @@ namespace SpotifyAPI.Web
         }
         else
         {
-          queryParams.Add(attribute.Key ?? prop.Name, value.ToString() ?? throw new Exception("ToString was null on a value"));
+          queryParams.Add(attribute.Key ?? prop.Name, value.ToString() ?? throw new APIException("ToString returned null for query parameter"));
         }
       }
     }
@@ -156,7 +156,7 @@ namespace SpotifyAPI.Web
   }
 
   [AttributeUsage(AttributeTargets.Property)]
-  public class QueryParamAttribute : Attribute
+  public sealed class QueryParamAttribute : Attribute
   {
     public string Key { get; }
 
@@ -167,7 +167,7 @@ namespace SpotifyAPI.Web
   }
 
   [AttributeUsage(AttributeTargets.Property)]
-  public class BodyParamAttribute : Attribute
+  public sealed class BodyParamAttribute : Attribute
   {
     public string Key { get; }
 
diff --git a/SpotifyAPI.Web/SpotifyAPI.Web.csproj b/SpotifyAPI.Web/SpotifyAPI.Web.csproj
index 6d78b384..f70019e4 100644
--- a/SpotifyAPI.Web/SpotifyAPI.Web.csproj
+++ b/SpotifyAPI.Web/SpotifyAPI.Web.csproj
@@ -35,9 +35,9 @@
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3">
       <PrivateAssets>None</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="3.3.2">
-      <PrivateAssets>all</PrivateAssets>
-      <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
-    </PackageReference>
   </ItemGroup>
+
+  <PropertyGroup>
+    <AnalysisMode>AllEnabledByDefault</AnalysisMode>
+  </PropertyGroup>
 </Project>
diff --git a/SpotifyAPI.Web/SpotifyUrls.cs b/SpotifyAPI.Web/SpotifyUrls.cs
index f0950000..b41364c4 100644
--- a/SpotifyAPI.Web/SpotifyUrls.cs
+++ b/SpotifyAPI.Web/SpotifyUrls.cs
@@ -3,13 +3,13 @@ namespace SpotifyAPI.Web
 {
   public static class SpotifyUrls
   {
-    static private readonly URIParameterFormatProvider _provider = new URIParameterFormatProvider();
+    static private readonly URIParameterFormatProvider _provider = new();
 
-    public static readonly Uri APIV1 = new Uri("https://api.spotify.com/v1/");
+    public static readonly Uri APIV1 = new("https://api.spotify.com/v1/");
 
-    public static readonly Uri Authorize = new Uri("https://accounts.spotify.com/authorize");
+    public static readonly Uri Authorize = new("https://accounts.spotify.com/authorize");
 
-    public static readonly Uri OAuthToken = new Uri("https://accounts.spotify.com/api/token");
+    public static readonly Uri OAuthToken = new("https://accounts.spotify.com/api/token");
 
     public static Uri Me() => EUri($"me");
 
@@ -125,6 +125,6 @@ namespace SpotifyAPI.Web
 
     public static Uri LibraryShows() => EUri($"me/shows");
 
-    private static Uri EUri(FormattableString path) => new Uri(path.ToString(_provider), UriKind.Relative);
+    private static Uri EUri(FormattableString path) => new(path.ToString(_provider), UriKind.Relative);
   }
 }
diff --git a/SpotifyAPI.Web/Util/Base64Util.cs b/SpotifyAPI.Web/Util/Base64Util.cs
index c2eb5a71..e1e91e1c 100644
--- a/SpotifyAPI.Web/Util/Base64Util.cs
+++ b/SpotifyAPI.Web/Util/Base64Util.cs
@@ -114,21 +114,17 @@ namespace SpotifyAPI.Web
 
     private static int GetNumBase64PaddingCharsToAddForDecode(int inputLength)
     {
-      switch (inputLength % 4)
+      return (inputLength % 4) switch
       {
-        case 0:
-          return 0;
-        case 2:
-          return 2;
-        case 3:
-          return 1;
-        default:
-          throw new FormatException(
-              string.Format(
-                  CultureInfo.CurrentCulture,
-                  WebEncoders_MalformedInput,
-                  inputLength));
-      }
+        0 => 0,
+        2 => 2,
+        3 => 1,
+        _ => throw new FormatException(
+      string.Format(
+          CultureInfo.CurrentCulture,
+          WebEncoders_MalformedInput,
+          inputLength)),
+      };
     }
   }
 
diff --git a/SpotifyAPI.Web/Util/PKCEUtil.cs b/SpotifyAPI.Web/Util/PKCEUtil.cs
index 73ec6b6f..55157a8d 100644
--- a/SpotifyAPI.Web/Util/PKCEUtil.cs
+++ b/SpotifyAPI.Web/Util/PKCEUtil.cs
@@ -52,22 +52,18 @@ namespace SpotifyAPI.Web
 
     private static string GenerateRandomURLSafeString(int length)
     {
-      using (var rng = new RNGCryptoServiceProvider())
-      {
-        var bit_count = length * 6;
-        var byte_count = (bit_count + 7) / 8; // rounded up
-        var bytes = new byte[byte_count];
-        rng.GetBytes(bytes);
-        return Base64Util.UrlEncode(bytes);
-      }
+      using var rng = new RNGCryptoServiceProvider();
+      var bit_count = length * 6;
+      var byte_count = (bit_count + 7) / 8; // rounded up
+      var bytes = new byte[byte_count];
+      rng.GetBytes(bytes);
+      return Base64Util.UrlEncode(bytes);
     }
 
     private static byte[] ComputeSHA256(string value)
     {
-      using (var hash = SHA256.Create())
-      {
-        return hash.ComputeHash(Encoding.UTF8.GetBytes(value));
-      }
+      using var hash = SHA256.Create();
+      return hash.ComputeHash(Encoding.UTF8.GetBytes(value));
     }
   }
 }
diff --git a/SpotifyAPI.Web/Util/StringAttribute.cs b/SpotifyAPI.Web/Util/StringAttribute.cs
index d54e39df..bc13301a 100644
--- a/SpotifyAPI.Web/Util/StringAttribute.cs
+++ b/SpotifyAPI.Web/Util/StringAttribute.cs
@@ -6,14 +6,14 @@ using System.Diagnostics.CodeAnalysis;
 namespace SpotifyAPI.Web
 {
   [AttributeUsage(AttributeTargets.Field)]
-  public class StringAttribute : Attribute
+  public sealed class StringAttribute : Attribute
   {
     public StringAttribute(string value)
     {
       Value = value;
     }
 
-    public string Value { get; set; }
+    public string Value { get; }
 
 #if NETSTANDARD2_0
     public static bool GetValue(Type enumType, Enum enumValue, out string? result)