Can't wait for KH4, though all I'd be able to do is read about it.
That aside, I decided the Entrance of the Xenoa: Lunar Shadow version should use a different tileset, so I'm currently trying to think something up that'll be fitting for it. Maybe a tileset from a past mod I worked on, I dunno.
As for Rave Story in particular, I think I only briefly loaded it up once. That has some custom levels, sprites, and maybe some new music too, right? As long as it doesn't have ASM hacks, you should be able to port it for the most part, but only the ORG music will work. Getting extra music to work for the "New" and "Remastered" soundtracks isn't as straightforward for CS+ mods as ORG music.