I would never define Maria, Aerith, Rinoa, or Yuna as "curvy".

Lulu, Beatrix, and Tifa were kinda curvy, but mostly they just had really big knockers and tiny tiny waists. Not really curvy in the same way as Chung Li is curvy. You don't really see Chung Li sized thighs on female characters these days.

To be honest, this isn't really something I've noticed or thought all that much about so it hasn't really impacted how I view or experience the games. And yeah, Asian countries lean on the skinny sized. I don't remember seeing one obese or fat person while I was visiting S. Korea. Chubby, occasionally, but mostly just lots of skinny people.

Besides, it's not like there are a lot of curvy male characters running around. Most of the guys are skinny too and all of them have six packs.