I would like them to do one of two things. Either:

A: Make me use my healing tools if you're gonna keep giving me so many. I have a massive arsenal of heals but I'm encouraged to only ever use my GCD healing when things are going horribly wrong. Otherwise it's all regen/OGCD heals and mindless 1 button damage spells.

B: Remove some of the obsolete healing tools (seriously, Cure I and Benefic I can just upgrade to their stronger versions, the RNG part of them isn't even worth it) that nobody uses and give healers more damage options.

I think the most fun I have ever had on a healer in any MMO was Rift's Chloromancer, which was a healer who had to be proactive because most of its healing was done through dealing damage and debuffing the enemy. It had spot heals, but they couldn't cover the entire demand for healing. I was excited for Sage when I heard it was "deal damage to heal" but it turns out Kardia is basically just a glorified regen on the tank.