The only QoL that I could think of for Living Dead is to add additional way to proc Walking Dead: receive enough damage equal to set amount of HP percentage (probably 100%) while Living Dead is active. Maybe extend the window of activation to 15s. This way, even if your healer goes into panic mode, your LD would still proc once that damage threshold is met. The good side of having external heal being able to pop your LD is in the event you cannot proc Walking Dead yourself (I.e. no target to attack, Down for the Count, stun, etc).

Hard disagree on adding more self sustenance to DRK. Anecdotally speaking I have never seen the need for extra sustenance in dungeon pulls as a DRK nor healers that could or could not be grieving. More than not, this is because of the combination of the following:
  1. Healer have no idea what and how Living Dead works.
  2. Healer is one of those 'omg tank's HP so low I need heal omgomg'-panickey healer.
  3. Healer wasn't paying attention.
I certainly know DRKs do not need that extra sustenance because I've survived through wall pulls in 'harder dungeons' as a DRK paired with a Freecure/Physick/Helios/Diagnosis Mage with AND without use of LD. If that low of a HPS can sustain the tank with known lowest sustenance, then the issue would've lied on combination of all 4 players' competency (bad healing practice, single targeting dps, bad tank cooldown rotation, etc).