I'm all for either: Cleric stance returning in it's old fashion (healing cut in half, damage increased by maybe a quarter) or each healer getting their own stances. Because both stances, and unique systems, accessible early on are really lacking. Just to clarify, for Stances would be turning your entire playstyle on it's head: Offering lucrative buffs, but also massive downsides making you think twice if it's really safe to do this. They could also either alter skills, or straight up make some skills only available when you're in the "high risk" stance. Best thing is not every healer would need to have something like this, I'm wanting this on SCH because that's the one I so enjoyed taking larger and larger risks with knowing I could keep the party safe while doing this.

I'd stop short of having all healers scale damage of INT, only just SCH. If not only to further to differentiate them, Scholar could solidify in it's Arcanist roots which carries the drawback of having damage scale of int, so you need swap the stats around depending on what you'd want to do in one or more stances. This could further be expanded upon with Fairies both offering different pet skills, but also affect or entirely change what skills you had available. The complete opposite of having Eos and Selene being color swaps and the skills themselves is on your own hotbar. Wish I could come up with something for WHM and AST, but experience there is limited to stories told by friends and forum-goers.