In my opinion, I dont see a massive problem with warrior as a tank, so to speak (though i think some skills should be changed, like storm's path haha, ill never use it, maybe if it did the same as skull sunder+heal and combo'd like HS>SP>BB), what i see is a synergy problem with healing and mp.

So, maybe if say, Defiance gave a +% permanent healing recieved increase, or each stack of wrath gave a +% healing recieved increase. Dunno what number% would be not OP, maybe 25% defiance and 5% each stack of wrath? who knows haha. But again, in my opinion, i just see a synergy problem between healers and their mp used to cure warrriors, and think if a healing received bonus can be balanced with paladins damage reduction, everything may be alright =P