As a healer it really pisses me off how much stress heroics place on the heals. If you think about ICC heroic fights, the healer is the star of the show. Heroic = Bosses have more health which means fights last longer so healers must heal longer, which can lead to running out of mana a lot sooner. Tanks take sometimes double the damage, which means healers have to really pay attention and drop big heals. I like healing heroics the challenge is fun, but i feel that DPS and sometimes tank arnt really being stressed enough. After watching footage of cata heroic 5 mans... I feel there should be a balance... More 1 shot mechanics to punish dps, more enrages... Tanks for most fights are fine, i see tanks doing their thing. With threat decay, managing cd's, they have enough work. But most fights are tank and spank, you can spam attacks and accept heals.
Stonecore has it down, those fights are pretty balanced... I like that.