Living Dead is among the best Invulns as of today.

Second shortest cooldown and provides a heal equal to your max HP over 5 GCDs.
Holmgang remains the king as it synergize perfectly with WAR very short CDs and strong healing.

The only weakness with those are continuous damage and lack of immunity to damage down.
But it's niche and not worth the extra minutes on Bolide and Hallowed ground. HG being a 7 minutes cooldown and its terrible synergy with PLD's kit makes it the worst Invuln.
IMO Bolide and HG should at least see their cds reduced by 60s. Living Dead would still be stronger but Bolide could compete in some niches.