In a similar fashion I've been having regular mana problems with my pally, though the shammies don't suffer on mana much at all, even though chain lightning is in their click sequence. Mana totem/Kings is the approach I use.

My pally just dinged 70 (he has heirlooms while the shammies don't), most mobs die before judging returns much mana. Is it simly a matter of my regen will be in the toilet until I get divine plea next level?