Imo you shouldn't die if not healed enough.
1 of 2 things should happen:
a) you get the double weakness effect. that would lower your damage output a lot. Also if you are not getting healed enough you might just die from the next attack anyway.
b) the DRK would get a vulnerability debuff. that way you would take a lot of damage and might die afterwards anyway.

It worked out for 2 yrs and with Benediction on a shorter CD it's probably easier to handle now. But not everyone has a whm.
Also with how much PLD improved and Hallowed Ground still being the same on top of that, Living Dead really deserves a buff (a shorter recast probably) or as described above a less harsh penalty.