The 2 handed execute is the problem with its 50% starting point. Other executes are fine.
Radiant Destruction could be named as well, but I personally rarely encounter it, so unsure how big of a problem it is.
I welcome a higher damage meta though. I hope people will finally come out of their shell and play proper builds that do not rely on the stacking of several ultimates.
Casting executioner at anywhere above 30% is a waste of a GCD
Do you have a formula how DMG increases with %HP?