You can purify living dead off you when you hit 1 HP. Just pop all your CD's because they will try to last hit you and after your healer's back in action, just purify it off. It's a good opportunity to draw people in to your base. So there's your healthier way of removing the debuff.

DRK's in a bad spot. I just dont think it was a well thought out tank. AST is very pretty and is very functional and MCH feels like a more reliable BRD. DRK just awkwardly sits between the two others.

Honestly to make DRK a viable option in PvP they'll have to rethink the entire job. There's just too much they have in their toolkit that is nowhere near as good as WAR or PLD. They probably even did the STR nerf specifically because they didn't want to re-do DRK - even Yoshi P said he wanted WAR to be the "big DPS" tank and look where it is now. Not big DPS, just burstier.