wouldn't it be closer to wario world if you did somethign like this.
create a save state at the beginning of each level right at the moment that you take control (after music)
Run a random save state game for X frames
The adding a hiscore file that will or cheat system that will check to see if the score and players is over a value when the frames are done?
If the person does, it loads another game and loads the save state.
I haven't really played much warioworld (own it for wii, and hated it).
Anyway, might be a fun mame version.