Hoping for a slight Abyssal Drain CD reduction.

[Martine]

With the current design I think they are wanting to keep the tank healing cooldowns on the same timer.

Warrior equilibrium is an immediate 1200 potency heal oGCD with no damage.
Gunbreaker is a 1200 oGCD potency heal over 18s.
Paladin requires either hard casting or using their DPS burst CD to heal which still occupies the GCD.
Dark Knight is the only one with damage associated with it, dealing equal potency healing as Warrior/Gunbreaker at 6 targets.

It's a good observation, though the downside is that we don't always have 6 targets, so it can fairly often be the weakest of the sustain. WAR, GNB, and PLD heals are all just as capable on bosses.

Edit: I should mention that I'm cool with the others having better boss self heals, I would just like a bit off my previous AoE sustain back.