So I think I ended up going hard mode on the final boss by electing to use my Class Change item on my healing mage, Yuko. Her new skill, Curse, is basically useless against the final boss, and it's extremely hard to go any further due to the absolutely massive CM cost to level up to the new skills. 30k when a good battle might give 1500? Not very viable.
Not helping matters is the boss' desperation mode activating at half health. It goes from single attacks and pretty potent attacks with Paralysis; to hit-all magic, a nine-hit combo that hits random targets, the paralysis attack, a 1.5 turn attack that is instant death if you don't have Ran get a Guard going (and will wipe anyone who's Paralyzed if she can't guard), and worst of all, an attack which hits all four characters with the four status ailments - Poison, Paralysis, Confusion, and Switch Ban.
Did I mention it gets two attacks per turn?
I get all of two Group Remedies, with no chance of getting more. Yuko might be able to heal, but you have to either have her in the party and burn a Remedy first, or burn the Remedy and swap her in. Either way, you're extremely vulnerable, since you use up your one item use per turn to get heals going - and if she got swapped in Paralyzed, you have to pray for a miracle.
Did I mention it has a second attack? If it used the status ailment one in the same turn as pretty much anything else, everyone will be hurting like mad. The only way to guarantee heals is bringing in Yuko and getting an X Heal off, which has guaranteed priority over the enemy.