As far as a Druid being a better healer though than a Priest I would say not really. While druids have more mobile heals thru Lifebloom and Rejev Healing Touch I feel is rather lack luster to Greater Heal. MotW is a decent buff though not as good as PW:F is for Locks. More Sta is always great. My biggest problem with Druids is how sucky Tranquility is. Also until 80 and the new Revive rez talent you would pretty much be dependant on Soulstones for rez.

I wonder though about the Shadow Priest as the extra DPS and Mana Battery would be nice.