Oh no I completely disagree. You dont spam heals needlessly just to get a potency increase, you are structuring your healing to get the most out of your kit, almost like a rotation. Just like how for DRG you wouldnt use Lifesurge (or whatever the guarenteed crit ability is called) just whenever it comes up, you try to make sure it is on your hardest hitting GCD to get the most out of it.
The lack of synergy with other abilities results in huge waves of damage being met with near instant recovery of that damage in about 2-3 seconds, so about 1 GCD and 1 oGCD. Healers in this aspect are less about healing and more about meeting HP checks, then continuing the brain dead nature of their dps kit, which again, the simplicity of which is a problem because healers have an extreme excess of downtime from healing.
In short, right now, Healers spend more time (GCDs) dealing damage than healing, and because of this players want more in-depth DPS kits for healers because essentially they are DPS, that just happen to heal to meet these HP checks thrown at them.
So, do you want to play a DPS that heals, or a Healer that can DPS?
I play healer sometimes in FFXIV, but I main Healer in WoW as a Holy Priest. As a Holy Priest, in terms of what i can do when I DPS, I have:
Smite - Deals Single Target Damage
Holy Fire - Deals Single Target Damage and applies a short DoT
Shadow Word: Pain - DoT Damage.
Thats it.
On a Normal mode Raid, I spend 90% of my time healing constantly, when I dont need to heal, I reapply SW:Pain and Holy Fire. I find it really fun and rewarding.
In FFXIV, I spend 90% of my time spamming Broil and Bio and when Huge raid damage comes out, I use 2 heals and poff! The damage is gone! I get to spam Broil and Bio again.
You're kinda asking for a DPS that has to stop their rotation (even if it isnt invasive to whatever combo they have going on aside from straight up stopping dealing damage for a while) to heal. Which if SE wants to do that, all power to them. But you will see every DPS turn into a little mini healer and Tanks self-sustain even harder to cover the loss of an actual healer, cause... well, you wouldnt want to interrupt their DPS right?