Some stories can’t be told without a boatload of characters. My current WIP is definitely in that category. There are so many things going on, to tell the story requires a huge cast. I’ve read similar novels where it sometimes got really difficult to remember who certain people were, unless they were somehow in context. In other words, some people relate to certain scenes and plot angles that make them stand out.
One way or the other, if your book is loaded with characters, one way you can do your readers a tremendous favor is to provide a dramatis personae. If you’re not familiar with that term, it’s a list of who and what each person is in the beginning of the story; a cast of characters, if you will. This is particularly useful if there is some blood relationship between your characters, which may be difficult to keep track of for the reader.