My suggestion would be to keep adding to this story. You could do several side stories that explore some of the other characters, just do it as a book 2, book 3, etc. If you did it that way, you could label it as "Managing A Metal Mouth, Book2: Cynthia's story", and add other stories as you write them. It would keep all the related stories together and still allow you to explore the different characters without having them all joined together in one story.