I made a post about the problems with making those stats scale here.
Hilariously enough, World of Magic used outcome 3, when it could have handled outcome 1 decently well because the entire map was one giant landmass, so it would be hard for super fast or super large blasts to be oppressive since it was so easy to run away.
Regeneration could be another stat. It’s an arbitrary numeric value instead of something that translates into physically messing with the collisions of the game, and health gained from the Defense stat no longer increases regeneration, so Defense doesn’t have that stat built-in into it anymore.