Guardian of the Ancient Kings
Didn't see that coming did you? Nope. We need a rework of the talents, and the obvious, and of course awesome, route to go is making the holy tree a pet based healer. How could this work you ask? Well.
Have our 31 point talent make GotAK have no cooldown, and last forever. Secondly we would need to change the way that GotAK works for holy, I think it should do what it currently does(heal the target with the same heal you just did) but maybe for 40% and lose the AOE bonus.The GotAK would scale with your stats. Perhaps the pet could replace Divine Plea and somehow be a regen tool? I don't know... but I want it. This game has no pet class healers. Maybe for good reason, but can we not agree that it would be awesome?
This would mix it up as far as healers go, the class would need tweaking and some baseline heals reduced to compensate.