I rarely use improv. As a capstone it'd fairly weak, but at least the rest of the job has a strong note to it. I really only use improv in phase transitions. Eden 1 Savage is about the first time I felt it had a use because there was a period of doing nothing whilst healers get people back to health, though the impact isn't felt.

Curing Waltz to me is a clutch heal, if I see health is low, its just a nice to have, my healer instincts usually kick in to use it. Because it's insta cast, I find it's worth using in those situations. But I guess it's that, both are situational.

I wouldn't mind a potency boost BUT normally that kind of thing means SE nerf something else, if it'd be the case, then I don't feel strongly enough for them to not adjust something we need because 'balance'.