Red Mage use Casting gear!!

[Yonanja]

I think they will share gear with the other two casters.

Why ?
Because adding another new gear category would dilute the loot pool too much.

Considering how tomestones work currently, and is extremely likely to keep working in 4.0 onwards, I don't think SE really cares all that much about bloating the lootdrops from chests, since I'm pretty sure that most peoples gear comes from tokens of one kind or another.