They could start by nerfing Edgar's super broken tools.
YOU TAKE THAT BACK
Besides, you can't just nerf his tools since he's only part of the problem. You'd have to nerf Sabin's Blitzes, Shadow's Throw, Cyan's (yes even Cyan) SwdTech, some of Locke's Boomerang weapons, cut Gau's Rage list to a more sane number, debreak Relm's Sketch, lower MagPwr's effectiveness, make learn-able spell lists individualized, nerf Cure 2 and Cure 3, ditch Ultima altogether (or make it enemy exclusive), start making enemies stronger before the Magi-Tek Factory, and maybe nerf some of the female exclusive equipment (or at least make them harder to come by).