Sorry I'm posting so late-- it's been quite the busy day!
So really quickly I just want to share something I think will help with your WIP, whether you're revising or just getting started. So go grab a piece of paper and a pen, and follow along :)
First, I want you to make three columns. Got it? Good. Now in the first column, write your Main Character's full name (or names' if you have a dual POV). In the second column, write the full names of your secondary characters, the ones that interact directly with your MC to further the plot or his/her story. In the last column, write down the names of all the periphery characters, the ones that show up once or twice but really have no significant impact on the story.
Good. There are two reasons for this. First, you'll catch any names that are way too similar, and can change them. Second, you can figure out if there are any characters you can merge or get rid of altogether. Make sure the characters that are there NEED to be there-- there needs to be a reason, big or small, for each one's continued existence.
Next, I want you to write out the main plot of your story-- in one sentence, if possible. Then, I want you to write out your subplots. All of them. Take away any that aren't strong, or add some if need be. Work out your character arcs this way, as well as your story arcs.
This is your new, starting outline for your novel. Doing this helped me tighten my novel significantly as I began to revise it. I caught names that were too similar, and really weeded out the unnecessary characters.
Good luck on your WIPs, and happy writing!