I will just throw this out there as an opinion of a pre 1.2 healing Mercenary. (I was forced to go DPS because of the need for DPS in our Ops groups)
In champion gear (no battle master gear at all) I could out heal 4 people attacking me in PVP. That was so god damned over powered it felt like cheating!. Half a warzone team should not be out-healed by 1 healer healing himself. Especially while being interrupted. I do not consider myself a "good" player, nor do I have a great PC (yet ). I feel I always need to improve. I am just an average player.
I will say I do not know the state of a healer these days, but I will say a "balance" was definitely called for. If they really are in the sorry state many of you say they are in, that was just uncalled for then.
I will switch back to healer at some point. I don't know if it will be after a fix though.
As a post 1.2 Arsenal Mercenary, I am rarely ever at the bottom of the medals list. I do die my fair share, but I res, and get back out there. I do have trouble staying alive against a marauder and Operatives, but oh well. I kill just as many of them as they kill me. I still manage to rack up close to the top damage and kills each match. I am in mixed Battle master/old champion and some recruit gear now. I try to never be alone, it helps. I always queue solo.
I will agree with most people here, a proper balance is called for.