I haven't done any heroic 3's yet, so I can't exactly say, but as an all-rounder healer (meaning that's really the only thing I truly know how to play is healer) I agree with the original poster. Yeah, fights that are more complex are fun, but when your entire group relies on you and only you as the healer for those fights, it's stressful, man. Because some of us don't want to be either kicked, (well, in the old days when they had pugs) or chewed out or whatever. As someone who mained fury for almost 20 years, it sucks when people say, "oh such and such class is better so we're going to take them." I have memories of people choosing Wardens over me, because they were "the better class."
It's not fun for everyone. And like I said, haven't done H3's yet. I am not necessarily for class balance, but from the perspective of a healer, (and with all the cure curse crap there is in the game now) I'm all for something that makes curing easier.