Curses! KL got here first again! I have no luck with this thing....
Yep KL is right again... Although considerably, Tarzan COULD come back, if they think of a new plot... Like.... off the top of my head.... Creatures are disappearing in the jungle, and Jane is among the lost ones, and now you have to go find out what is causing it. We would get to meat Tantor and Her father hopefully... But anyway that would be doubtful because Deep Jungle wasn't even in CoM (Not even the Jungle King Key!). I suspect the legal rights of Tarzan were involved.... Still it could be replaced with a similar world (Jungle book is a possiblility) or Square could go nuts and fuse the two.... But that is highly doubtful. Anyway I just want the Jungle key back again....
Also Atlantica is possible, perhaps on a similar version of the First movie story, only with a new Villian... otherwise they could bring back Ursala, but it would be hard for her to take her voice again....
Wonderland... Meh... I didn't like it, but it is a possiblity...
Peter Pan I could see... but they would have to work on the story (KL, the second one wouldn't work because of the Time deal, it would have to be Ten years later for it to even be concievable... Unless Time in Neverland is faster than on the other worlds...).
Monstro... Meh... It has been used up... but they need to give Jiminy a good role....
End of the world is possible, but I think the last world will be the deep dive one (Appearantly home to the Organization). Remeber, the new serious enemy has to be dealt with last, so the ending could take place there instead. But it could return, but it most likely will be changed. After all, New world were destroyed to make it.
And as for Traverse Town.... Well where else would you meet Leon and his pals?
That about raps it up I think... Feel free to argue!