Unpopular opinion, but DRK shouldn't get any self Healing abilities at all, its way more than enough that we got WAR and PLD for this kind of thing.

Instead, DRK should get something else that fits more with its nature (in terms of lore) as a "selfless tank who protects the weak". If we give DRK more Healing abilities, it will always be a weak WAR in design and too similar in design.

Sole Survivor should grant something like bonus stats or so the more Team mates are dead on the floor ( with the idea that a near wipe can still be turned arround) and Living Dead, should either get its Healing recieved Limit reduced to 50%, or allow the DRK to continue attacking for like 10sec with 0 HP after having died with it being active (invul lasts 10sec, the buff for turning into "zombie mode" lasts 20sec).