Well I wonder if there are any hacks/patches/mods out there that alter either the spells taught by a particular Esper or the speed at which the Esper teaches a spell?

If Tritoch's spells were taught at 2x I'd have nothing to complain about. It's the fact that Fire 3 can be learned three times as fast as Ice 3 and Bolt 3 that I find to be lopsided.