Kingdom Hearts is a fun series of games. For anyone that doesn't know it is an RPG (role playing game) that uses characters from various franchises owned by Disney and Square Enix. It is a fun, and lighthearted game series. However it could be improved.
1. Firstly, it would be nice to see more franchises used. Square Enix has used a few Final Fantasy characters, but it would be nice more. The Dragon Quest series comes to mind. Disney own Marvel comics, and Star Wars, be nice to see either one of them in the mix. The Silver Surfer seems like a good fit.
2. Character from franchises having character arcs that aren't identical to the ones they have had in movies.
3. Maybe a little darker tone. Huey Dewey and Louie are usually running a shop of some kind. What if we found out it was just a front for a drug empire, or a prostitution ring. It would give you a little more to think about after playing the game.
4. The ability to allow worlds that annoy you to blink out into nothingness.
5. An admission that everything that is happening within the universe of the games are just a fantasy a child is escaping to while being abused/molested. Deep down, you know that is what is going on. Poor Sora... might be why his name is "Sore-a".