reasons why other worlds could return
Wonderland: If the villians are going after the Princesses again then Alice is in trouble. Also its a chance to see more of the Mad Hatter than a painting, and remember there was more in the film than the Queen of hearts.
Deep Jungle: We may have done all the stuff from the Tarzan movie but whats to say the TV show doesn't play a part, we may also get to see Prof Porter, Tantor and others. Perhaps the plot will be more KH character centred.
Atlantica: not sure I have a spasific reason, maybe relate it more to getting Ariel on land? Perhaps giving her a different fighting style while on land, just as long as she doesn't try to fight in that dress.
Neverland: Now just because theres Pirates of the Carrabian doesn't mean theres not going to be a Neverland world, just in this it can be set OFF the Pirate ship. Meet the lost boys, Mermaids, Tigerlilly and Wendys brothers. We want to see Neverland itself this time.
Traverse Town: People who've lost their worlds go there, Just because Leon and co will be in Hallow Bastian doesn't mean this place will be left out. Perhaps it was part of another world and you vist that world? Besides it and Twilight Town are hardly the same