I know! In the next game they should have it so that you get to make your own reality TV show called "Atlantica Idol"! :O

*is being sarcastic*

As for continuity, the idea of a Keyblade War would be rather interesting. The secret ending to KHII:FM+ that if it was referring to a future game that Mickey would be most likely present, though it almost seemed to me that it was a younger version of him. Something along of the lines of pre-KH timeline would be interesting. Maybe eventually something about when the first Keyblade appeared would be cool too.

Besides that maybe some more FF cameos would be nice, better yet they could always have one the worlds be one of the actual FF worlds, though that might be strenuous on said world's original plot. As for Disney worlds, Sword in the Stone would be neat, or Robin Hood.