If RDM support is holding back it's DPS, maybe there needs to be a mechanic to discourage it's use over time. Perhaps a stacking buff, one stack given every 30 seconds to a max of three, where Verraise can only be cast at the cost of all three stacks, Vercure costs one? That way there is still utility available to RDM but it's limited, and DPS can be improved to compensate.

Either that or improve the utility and keep DPS low. I always thought there should be incentive for aligning to White or Black magic. Maybe at 100 white mana your melee combo gives a small AoE heal for each enchanted ability, 100 black mana gives a small AoE MP restore? Or a small aoe shield or something (Phalanx effect?)