Since this book is about the Salem Witch Trials, you will do best to do some film research on the topic. By watching other Salem Trial based films, you will be able to formulate a new character who is similar to John Proctor but different in many ways. Use the various film settings and themes in order to develop your own original idea of the story, using new information garnered from the films you watched and additional research that you should be doing for the story. The best way to develop your own story is to immerse yourself in stories and movies about that period of time. Take inspiration from their characters and then develop your own original story. Kind of like how E.L. James took inspiration from the characters in Twilight and came up with the Fifty Shades storyline in the process. That is what you should be doing here.