It's why all healing changes are going to be a massive undertaking, as it has to also be re-worked for all older content, and in particular the lack of incoming damage vs our overloaded healer kits is an issue you have to start fixing at lvl50 at the very latest, possibly much earlier.

That is:

* Massively increase damage frequency on the group, and in particular unreliable output. Initially keep damage lower, of course, but make it clear that there's always "something" to heal.
* Massively curb ability and in particular oGCD proliferation in healer kits. Cut the kits down heavily. There's no reason to have 2-4 oGCDs that ultimately all cause AoE healing, one is more than enough, make it stronger and more unique to compensate.
* Ideally compensate for the previous point by establishing some interaction between damage tools and healing tools that encourage interweaving both abilities.

But of course, again, that requires going back through all previous fights and re-doing much of them entirely.