I'd like to also point out, AVALANCHE (since we seem to be using these names to signify the group as opposed to the mooks who get killed at some point in the story). took out a single dragon in Advent Children. The Returners, in the World of Ruin, take out 8 dragons. And two demon-thingies.

Also, Sephiroth's sword-play isn't as utterly impressive as people seem to make it out to be. One of the fun things about magic, its damage is generally higher and its range is generally longer. Kefka has the MP to spare. I don't think Sephy's sword's winning him anything here.

And Kefka uses just as much of his own power as Sephiroth. Sephiroth uses Jenova and the Lifestream, Kefka uses Espers and the Statues.