I think healers get TONS of commendations - its DPS classes I feel bad for. Aside from seeing who's highest on the aggro table, their contribution is more subtle than constantly fluctuating health bars and flashy buffs/healer AoEs. I have a lot of comms, and I play 270/270 AST/SMN about equally. I'd say 80% or more are from healing (I swear I don't suck at SMN! XD). When I give out comms, I always try to consider the DPS first.