I'm totally insane. With that said, why don't we turn cleric stance from it's current form to something like permanent -XX% healing while giving an AOE aura around them that allows the group to do +XX% damage within range.
Redo the damage stat from INT to MND on the healer.
This solves new/uncomfortable healers, they don't need to turn on cleric stance.
This solves elite healers that can heal with the penalty, give a group damage buff, and still contribute their own dps.
This solves healers who want to be heal only (out of principle), at least they can turn on the buff and spam cures like they want but the group still gets the benefit.
Of course the scaling needs to be figured out so it doesn't become insanely OP.