Here's my team first time I played the game:

Sabin was level 89 or so, the highest level guy in the team. Sure, 89 is waaaaaay over kill. He was equipped with the good ole' Genji Glove + Offering.

Shadow was 40+. I liked him because throwing stuffs seemed to actually deal damage.

Edgar was 42+, liked his drill but most of all that debilitator.

Terra was 35+. I didn't wanna level her up much since your know, Morph doubles your damage? That coupled with Edgar's debilitator...

Celes is 35+ probably is my next favorite due to her Runic abilities. HOwever, Runic does get more useless till the end

Gogo (50+) is next because he is...a mimic =/ Though his stats suck but...hey, at least I know I can rely on himfor many stuffs.

Gau (32+) might be next. Catscratch just rocks...and his other rages rocked too. Leveling him up is a pain tho at times.

Locke (40+) is nice to have to steal all the goodies for Shadow to throw (yeah, I threw my rare collection of swords away). Capture rocks. Wonder if anyone tried zombying Locke with Valiant Knife just when he was low on hp?

Strago (28+) is low on my list. Might be because I hate blue magic.

Relm (28+). Urg?

Umaro (35+) This guy packs a punch. Too bad he can't be controlled...

Setzer (28+) My SNES emulator has a problem with the slot but GP Rain is good at the end of the levels :P, thanks to the Cactus I fought many times. 10k GP each

Overall, I sorta kicked Kefka's ass with one casaulty (stupid instant death). My team is: Sabin, Edgar, Shadow, Terra (Terra died, replaced by Celes, luckily)

I know my team was way overpowered so I started another game and didn't bother to level up. YES, it is possible to win when you are around level 35. I've done it, so can you