I *LOVE* the healers! Being on (basically) my first character at level 33 with a DPS (tank minor), I'm sure I am not anywhere near efficient at my role, but I sure appreciate the healers and do everything I can to keep the aggro off them. If necessary, I've mass taunted mobs (when I'm not playing the tank role) just to buy the others a few seconds to recover, wherein often times they will and we proceed (after they pick my sorry butt off the floor a time or two).
I have only done pick-up groups, but organized parties sounds like it would be fun. Thus far, even with frustrations with folks charging in without any crowd control, breaking crowd control, or not focusing on the right order of targets, I've yet to experience a cranky member.
My primary character, who I suppose is now an alternate since I abandoned him at an early level due to some system glitches, is a healer, and I look forward to using him in groups once I'm through my class storyline.