AoE dots needs to removed from the combos.
(Why would I do that with a bunch of mobs, then they can be slept and oh look my whole party just wiped)

　
∟BLM Mag. 1 O Deals lightning damage to target.Combo: THM Magic 9, Bonus: Lower health yields greater damage.
The bonus needs to be removed on this because this is rarely going to happen. There will be white mages with OCD that will heal me till I am full of hp. Or I am gonna piss someone off by spamming sacrifice to obtain that low HP.

No cool ability like White-Mage where we use all our MP to unleash a powerful attack?

So White mage has Benediction, Chain spell, Holyshi... Holyga,, and an ability to increase there magic attack potency.

And we get the ability to switch our HP and Mp
(Not to useful at all if you MP exceeds your Hp, and a good Wizard knows when not to get hit so there won't be a need to switch my HP/MP)

And restore HP with the next magic attack spells... (seriously?)