You all complain that Pale Masters are overpowered.
I however, think that these silly robot mages with the ability to heal themselves 15 different ways is the main, root problem.
A robot should not be the best class for an arcane. An arcane should never have healing ability, unless they sacrifice a lot and specialize for it (via multiclassing, or becoming an undead).
Turbine broke the game way back then, I propose a fix.
Remove all repair spells from arcane spell books.
You can give them to clerics, how about that. the healers.
And then forget about your silly 'Hard to Kill' mechanic. The problem will solve itself.