Best of luck! I experimented with making use of Golbez instead of Quistis as to max him out, and it seems that as long as you have a fairly useful attacker, and you use Vanille to dispel the Def buff, then replace her or your more useless character with Quistis, you can clear a run pretty quickly, around 3-4 min, even if Vanille and your weak link are completely useless!
Just try to make sure you follow any Quistis characters currently following you back, so they can stick around for Five turns and really lay on the Damage, and try to get her EX off with 2 uses of Degenerator Whip left, so you can make the most of her buff.
This will get trickier with Shiva, since she splits into two, and it becomes this huge pain in the kupo, but Ifrit is at least pretty easy to damage with his Def buff taken out.
