Okay so I just want to flesh this out a little bit, I would envision this game as being a fully fledged gummi ship exploration/shooter game, where the protagonists (I think there should be 4, 1 disney characters, 1 Square character and 2 OC's, but it's not a solid thing). I think all the protagonists should be people who lost their worlds during/before KH1, perhaps around the same time RG fell, so they've all been together for quite some time.
Generally speaking, this wouldn't be a game to advance the plot, rather a game to explore the world of KH. I'd rather it be character driven, perhaps one character finds his world never was restored, another realises they're happier with their crew than a world he doesn't recognise anymore etc etc I haven't fleshed it out too much but essentially each character would have their own arc that would be resolved over the course of the game. I think this would be a good game to let more minor characters have some time to shine, like perhaps Kytes from FF12 as an MC, and I think Bernard from the Rescuers would be a good fit here.
A lot of the locations would be space or ship centered, and I think it would be a good chance to include a lot of iconic FF airships, as well as Disney ones.
I just think it would be neat to have these misfits travel the world trying to find their homes and running into maybe the Tantalus group, or even Captain Hook who's inadvertently found himself flying through space, even though I envision most of the actual gameplay to be gummi ship style (in the vein of KH3) there would be plenty of options to board other ships/explore worlds and in those instances I would have a basic command menu style implemented (seeing as melee combat isn't the focus, I don't think we need all the bells and whistles, just tight, basic combos and spells/summons).
Anyway, it's the least likeliest idea to happen but I think it would be super interesting
