I main RDM, and yes it had mana issues.
Not like you would run out of MP if you used LD on CD but you lost the support to raise people whitout getting an adjust to the potency the job have.
Personally I would like that the buff was split 50/50, less mana cost (enough to raise 2-3 fine on a fight) and a bit of potency buff to deal more damage so I dont see enrage everytime in E2S..
We are back as Rezmage