Kingdom Hearts 3: 10 Worlds Fans DON'T Want To See
2. Treasure Planet
There's no arguing here- Treasure Planet would be an amazing choice for Kingdom Hearts 3.
As confusing as that sounds, the presence of a Pirates of the Caribbean world might mean that having too many similar worlds could be an issue.
One of the biggest things that Kingdom Hearts has always done is try and diversify the worlds that it chooses to include in each game, with a clear goal on making sure that no two worlds have similar themes and gameplay features. With Pirates already in the game and Treasure Planet having that as a big influence, it feels really unlikely we'll get both in the game.
If a Treasure Planet world could find a way to properly differentiate itself from Pirates then it could definitely work, but it could be made fairly redundant and is therefore a pretty big risk as a world. This is really a shame, but let's keep it to just one pirate adventure this time.
For the record, Treasure Planet over Pirates any day.