Considering that all the FF7&8 characters are just bizzare DBZ-fusion hybrids of the FF6 characters? And there were a LOT of them... the one thing I didn't like about 6... 7&8 were good to reduce the numbers down to something more manageable. But 8 needed more character developement. Take the FF6, Chrono Trigger, and Legend of Dragoon, and you have all you'll ever need for any RPG, EVER.
Really.... you don't even have to try and figure that out... I'll even break it down nice and neat. But I'm lazy, you figure out the FF7 chars on your own, this is a FF8 forum, and, again, I'm lazy. And that's NOT including Wedge, Biggs, and Cid- they just like popping up everywhere reguardless.

Squall: Mix Shadow in with a little Locke and a touch of Sabin.
Rinoa: Terra, and not even cleverly disquised. With Shadow's dog.
Quistis: Celeste, pure and simple.
Irvine: Setzer and Edgar
Selphie: Relm, mostly... a little Gau... and some stereotypical ditz.
Zell: A little Edgar, a lot Sabin