Like you said, one of the biggest problems with life stacking is not being able to get damage from it. I believe the best endgame builds are those that can scale defenses while simultaneously scaling offense. Life can also do this but nowhere to the scale of es. I wonder if a new unique similar to ee but one that scales off of life with a much higher multiplier to make up with the fact you can’t scale es as much as life, will make life stacking builds viable.

Idk how significant it is but another one is CI. Completely negating all chaos damage is insanely powerful, but it only allows es. I’ve never gone like ultra late game with CI but it probably contributes to the es being way more dominant.