How about having a new kind of RPG.
You control Super Heroes. It could have all kinds of them. Many including Super Man, Spider-Man, Plastic Man, and Thing. You have to gain experience to be able to use your super powers & weapons. Interactions with supporting characters is important. The main enemies are Darkseid & Galactus. You travel through the world & planets. How does it sound?
Well a Paper based RPG already exists for that kind of game. It''s called DC Super heroes, and to do that sort of game, would mean getting Marvel AND DC to agree....if I remember rightly, that is a pretty tough feat. Sorry if I am wrong, haven''t dealt in the world of superheroes for about 5 yrs now!
The game had "experience" and all the powers anyone ever had in the DC universe, you could use a points based system to build these up. What I am saying, is that you are close to copying exactly what someone has already done.....just trying to help.
PS Darkseid was my favourite character, got loads of mags with him in.