The ties to Disney, I'm not so sure, but with the voice acting, if they ever have an IJ world, they'll do the same thing as they did with Jack Sparrow and get a different actor (unless Harrison would be willing). And I do not mean the ride at Disneyland for the primary story of the world. Raiders of the Lost Ark would be fitting. Just think:
Keyblade: A sweet mix of ancient treasure and archaeological stuff.
Bosses/Enemies: Nazis, Heartless looking like little Nazi commandos, snake Heartless in the temple of the Ark, a big snake Heartless for the first boss, and other elements related to the movie.
Limit: Sora grabs to the end of Indy's whip, and while he spins around, Sora sweeps up and hits the enemies (it'll be tricky because you'd have to make Sora hit the enemies while keeping him in the air with Indy in the first place). To finish, Sora and Indy blast everything in sight; Sora with magic, Indy with his gun.
And the place is bound to have plenty of stuff, like in Indy's study, where he's found who knows what from his previous adventures, and the temples and digsites.
A little info on Indy 4: It's probably going to be CG. I think Lucas said something about it on Wikipedia.com.
But you haters have no idea what they could think up with this idea.
