Umm... Here I tell you what who is in the game, and what they do now.

Kimahri: He's the leader of the ronso tribe now. He's the one that found the sphere, that started Yuna and Rikku's journey.

Lulu & Wakka: There still in besaid. They're married now and are expecting a baby.

Brother: He's in the same sphere searching clan as rikku and yuna.

I think thats everyone...