Personally, I'd like to see self heals also raise the max HP, equal to whats healed (like thrall) for roughly 10-20 seconds.

Self heals wouldn't be wasted completely, but also can still be used at incorrect times. (aka doesnt help to use it at full HP, and then lose it before getting hit.)
And a consistent amount of +healing received, regardless of wrath. (like 10% with defiance, and then 1% with each stack of wrath)