I’m not entirely sure what you’re trying to get at here.
The problem we have is that healers aren’t fun to play, not any difference in their raid buffing ability.
Only when things are going poorly can we actually use our full kit (including GCDs), so our top level of skill involves boring Glare/Broil/Malefic spam.
Either encounter design has to change (but that has many drawbacks) or our damaging kit needs to be filled out beyond just level 4.