I suppose something they could do, is to improve the interactivity of healers during healing downtime. Either by making DPS more than just Stone/Ruin/Malefic spam or by providing skills that apply buffs/debuffs (Though that may end up with the "Meta" being to keep 100% uptime of said buffs/debuffs even during healing)

Then they could make Cleric Stance, the same long CD short duration buff, but enhance it with more damage output AND a conversion of damage done to healing to allies. Meaning that you don't need to worry about needing to stop DPSing to heal for the duration (Or other such things like old Cleric Stance meaning you give up healing temporarily)

Thus, the healer playstyle would have this CD to play around, finding the opportune times to let loose and blast away, while the rest of the time, they heal like normal and just have a more engaging DPS rotation when there's not much to heal.