We've had massive mileage at higher levels out of the healing domain. The granted power is passable. However, the real kicker has been using it with the feat (from Complete Divine?) that allows you to spend a turning attempt to spontaneously cast a domain spell... 'Heal on demand' has saved a large number of lives. Spontaneous Mass Heal is going to be way too useful!
I like the strength domain - granted power can be good for a few things... However, it's the spells: Enlarge is nice at lower levels and I've always had a soft spot for the 'xxxxx hand' spells at the higher levels, find them fun.