This. Regen hasn't felt like Regen since this change. I haven't been able to play a Regen character for very long since this change. (A long time I know.) I don't want to feel like a character who heals, I want to feel like a character who regenerates. I want chunks of my health bar to fill up as I'm fighting.
Regen suffers from being one the original defense sets so has a mix of stuff. It was one of the best sets originally, hence the nerf. But now it's a little meh. Performs fine, but doesn't really fulfill the flavor of the set the same way SR and Invul do. Moment of Glory still stands out as a weird power in the set, and had to be buffed how many times before people sorta started using it?
A lot of T9s in the defense sets need work though. They are very boring and/or skippable. So this isn't isolated to Regen.
What I want to see is the set having enough regeneration that I can cap it with some work from IO sets and slotting. Then the t9 lets me break the cap so that I'm healing so fast I can take the sustained damage for a bit.
Barring that, I would like any changes to Regen to make it feel like I'm regenerating rather than just interrupting my attacks to heal a bit.