You gotta remember it's about balanced characters. Your ideas of summoner sound cool, and I agree I would like to play this way, but if you can summon Ifrit big size into battle and control him to crush everything on the field with hellfire, then how is anyone else in battle supposed to matter? Otherwise summoning Ifrit would do the same damage as summoning the egis, but then people would complain your ifrit is too big and taking up too much of the screen. This is an MMO, and sadly everything you play has to fit into the MMO mold.