As for choosing the right spell and variable damage, I never really had that experience in heroic raiding in Cata. There was so much damage that with the exception of a few single target abilities that hit random people in the raid, it was pretty much an AOE healing spamfest and using mana restoring abilities on CD from the start. I used no better spell variety in tier 11 than I did in ICC. Lots of PoH, CoH, PoM, Renew, and a few random single target heals. How much thought is there behind "My mana is low!! AoE heals are expensive! The raid is getting hit with tons of unavoidable AOE!! My choices are then use cheap single target little heals and let raid die or use the effective, expensive AOE heal and hope that I keep them alive long enough the boss dies before I have nothing left"? How is that a more interesting "choice" than downranking or when to take advantage of the 5SR? I can't really think of ANY Cata heroic raid boss where the first option would have been the better choice.