Hey Varr,
I noted that as a gratis the poz healing is probably too much actually. I would not mind if its like Warfoged Repair Systems, "you give some you get some." If Pale masters have to trade negative hamp for poz vulnerability it would be fair enough, wonder who would choose that outside raiding setups tho.
I could see a couple of implementations:
I) Negative Energy Conduit (Select one of )
a) 10/20/30 negative healing amp
b) 10/20/40% positive healing vulnerability
II) Mixin enhancement: with Deathless Vigor - perfect label for this !?
10/20/30 hitpoints and 10/20/40% pozzz energy vulnerability
III) New enhancement (with tradeoffs)
20/30/50% pozz vulnerability
negative negative hamp 10/20/30 (dont apply math knowledge :P )
I think these are fair, in that it costs some points, -so no gratis, allows more building choice much like forged characters who can benefit from either more self repair or more incoming heals from others. Would maybe consider thematically to add 10-20% base for Zombie form, coz they arent all bone and floaty clothes.. something thematic to be healed on them.
with Varr, the poz healing is the single most important change -even tho the others are big too!