Easiest strategy:
HealerSpells
Prayer of Recovery (5;3): Cost 5 MP Single ally: SPI Attribute Helpful Spell
Subclass Spell that recovers a small amount of HP. The amount recovered is proportional to MAG and ATK.
Prayer of Good Health (5;3): Cost 5 MP Single ally: SPI Attribute Helpful Spell
Subclass Spell that cures PSN and TRR. Has a longer delay. Leveling up the skill will make it cure more ailments.
Skills
Healer's Knowledge (0;0): While the character keeps the subclass [Healer], the following bonus will be given: Slight increase in MP, MND, FIR, CLD, WND and NTR Resistances.
Efficient Cold Therapy (3;4): When you heal an ally, the amount recovered is increased by (SLv * 8 ) %
High Level Cold Therapy (5;3): When healing an ally, there is a (SLv * 10) % chance to heal any status ailments as well.
First Aid (3;3): When the skill holder takes a turn, he will recover (1 + SLv) % HP to all allies on the front line.
Devoted Care (1;8 ): When you dispel a status ailment on an ally, He will recover 25% HP as well.
I used Cold Therapy for 冷療, but it doesn't sound that great.