What made wizards uber in D20 was controlling the pace of combat. If anyone wanted to mess with a mage, you best have all good saves, and on top of that, catch him asleep.
With optional rules, spell power got silly. The only thing that allowed non-casters to compete at any level was the magic that the non-casters wielded.
Disjunction was one of the most broken spells in the game because it completely and utterly destroyed anyone but other casters. (terrible will saves.)
It is one of the reasons it was changed in Pathfinder to a MUCH less horrible fate for a melee type. Also trivial spells were able to get around most melee. Anyway, it's just my axe to grind against spell casters in PnP. There never was a contest.