Squall-He's stuck in my party so he's naturally stronger than everyone. And I guess Lionheart is rather pwnage...

Quistis-Degenerator, Homing Laser, White Wind, Mighty Guard (the FULL version). The only attacks I use, the only ones I need.

Zell-Now that I actually know how to use his limit break! Plus I had him junctioned with 100% zombie Status attack and I never felt like changing it.

The others aren't bad (Dark Shot, anyone? hehehe) but they aren't as good. Selphie's and Rinoa's are FAR too random, and I'm not going to use something I can't rely on in a pinch.