Okay for one, Role playing is not to be planned, it can have some planning but not complete or else that makes it a story. 2nd, i wouldnt let people be like Sora, Riku, instead have them create their own characters. You do need a plot. Also in role playing any thing can happen. Its like life, if you do somthing somthing happens, but if you do somthing else something else may happen.