I know people say Sephiroth is the most overrated FF villain, but Kefka comes up pretty close. Sephiroth had a much more detailed backstory and killed off a main character. He also blew up Saturn and Jupiter, as well as the sun during the final battle. Kefka was a lot more evil and villainous, but he gets too much credit. Ghestahl was the one who did most of the work. Kefka just waited for the right opportunity to overthrow him all Star Wars-ish. He also didn't even really destroy the world; the Warring Triad did. Anyone coulda moved a bunch statues. Heck, Shadow did it at the end of the Floating Continent.
Not to mention he freaks out at the sight of his own blood. And he is surprised that there is sand on his boots when they're WALKING THROUGH THE FREAKING DESERT.