I feel it's too early to tell at this point. The game still has two and half months before its release in Japan, plenty of time to reveal a ton of stuff and I actually doubt the stages will be high profile material. If memory serves me correct, they didn't even reveal Gabranth being in the original until almost a few weeks before the games release in Japan.

I'd say wait until SE does their fan event this month, cause that's where a lot of info is suppose to be released. I'm sure we'll get more info on Yuna as well as a few new characters but I wouldn't be surprised if SE leaked info about the game up until its release.