Jobs don't exist in isolation. They exist within a combat model. The two have to work together. You want jobs to change to fit the current combat model? Fair. I merely pointed out an alternate take, that the combat model should change to fit the current jobs. And really, that's a change that would benefit everyone, not just the healers, because if it is really about "the stress of mechanics", then let's see how everyone does when there's enough randomness that they can't plan out all the possibilities in advance.
I mean, the combat model, with all of its predictable scripting, is
boring. Piling on more DPS buttons to push will certainly give healers an opportunity to expend more of their attention span and effort, but, my two cents, is unlikely to actually do anything about that boredom unless you introduce
BLM-like failure states that are recognizable in all content (which is something that most all of the jobs lack).