I can appreciate that Healers have issues at the moment that need to be addressed. I think this partially comes down to mitigation inflation - the fact that with every expansion, supports fill up more and more of their toolkits with stronger on-demand defensive and sustain actions. There has also been a progressive shift away from resource management, such that there's no real risk of attrition. The end result is that you're generally at either 100% or 0%, so the actual act of 'healing' is superfluous.

I know that the current design of tanks is partially to blame for this, especially due to the rapid expansion of tank self-sustain this expansion. However, I don't see how changing tanks' combat style into something completely different would address healer problems. Tanks are generally good about raising their own issues.