I don't think the world choices really sell KH games. If that were the case, I wouldn't have touched KH3D (except for Hunchback, which wasn't even done justice).
I feel like Nomura should lean towards having a nice balance of CGI/classically animated/"out-there" (like The Caribbean, Tron, Halloween Town, Steamboat Willy, Fantasia etc) choices. Granted, KH3's "hottest" and most recent film was Big Hero 6, which was released 5 years before the game's release so I think that should justify that the films selected don't have to be the newest films. Tangled was selected and that was released about a decade before KH3, about the same length of time between Aladdin and KH1.
At this point, because of Disney's massive library now, just filling KH with the newest stuff would feel like a waste and a blatant/cruel ad to fans. World selection should come down to this: film's connection to main plot/Sora (or whoever is the protagonist in that game) and how fun/different the world will be to actually play in. I know Disney wants to advertise their properties non-stop and KH is basically us paying for that ad, but they need to take a step back and remember that this is a game and it's supposed to be fun. Thankfully, KH3 didn't go in the direction of advertising the newest films to us, but I sincerely hope that is not the direction for future titles.
I also don't like this negative opinion people have towards older worlds that have been revisited several times before like Agrabah, NeverLand, Halloween Town being in future titles - but that's a different thread.