Honestly, I think a better solution would be to make fights require consistent healing. While I am a serious advocate for healers to DPS whenever the fight allows, they shouldn't be spending near the amount of time they do in Cleric Stance. Making all forms of content hit harder allows the three healers to properly differentiate. Want to be a primary healer? Pick White Mage. Want to DPS more heavily and provide support heals/shields? Be a Scholar. Want to be a jack-of-all? Level up Astro. Right now, Savage is the only content where this even remotely comes into play.