Energy Shield(CI), Mind over Matter, Block and current player/boss HP values.

Let me start with the positives the game is a blast to play, it is fun and interactive up to the point where the PoE1 aspect takes over.

Energy shield values on gear alone allow for a very low investment double EHP pool to any build that chooses life which is only amplified by the incredibly high % increase on the skilltree.
Ontop of that you get to be immune to chaos damage altogether while also slapping on a shield with 40-50% baseblock, you then get to scale your mana which is a necessity due to the basemanacost increase at higher levels tick Mind over Matter, tripling your HP pool with the base investment of Intelligence required to use your gems and to top it all off you can put on an amulet giving you 20% of mana as added ES without any tradeoff since you can neglect the most annoying damage type resistance on gear.

Whereas if you choose life you're gonna have a hard time getting 4000HP with good gear if you're not a Gemling Legionnaire or Warrior.

The way the game scales at the moment with the choices players have is very much in favor of ES altogether, the reasoning for these values i assume was the recharge aspect which goes completely out of the window when paired with other options. Too high of a value to feel any threat from the game, scaled by monstrous % modifiers and effortless pairing with other options to turn builds into undying infinite scaling onetap machines.

The part of the game with the most testing is obviously the campaign, there were fixed values available of what players could get so the playing field was even.

With the current iteration of HP modifiers the playing field will never be even, it's impossible to scale bosses to be fair for either when the ceiling for both is so incredibly different.

The exceptions for this is the gemling legionnaire % stat stacking which allows him to do the same on Life. This interaction seems likely to be changed but that won't change the current flaw of the game not being balanced for ES/Mana/CI builds.

The bosses are fun to do, well designed but in the current game, they either get absolutely clapped, do nothing to the build due to absurd EHP or Onetap you despite wearing better gear than the ES counterpart that ignores every mechanic while doing triple your damage.

I get that this is early access but the disparity between 2 different things which achieve the same thing is impossible to overlook.

There is nothing fun and rewarding, when 2 different archetypes effectively play a different game.

If this game is ever supposed to be challenging, fun and interactive.
Then the playing field should be even, which it will never be when you can become immune to chaos by ticking a notable with no downside while also being 5x as tanky as HP characters.

What substance of the vaal did you masally skin embed?
Armor+HP is the highest passive EHP in game right now as bulk of hits are physical.
ES has the easier overflow option (gem thats win more and useless against bosses unless minion build), but it exists in unique form (Couture of Crimson) to pick up for HP instead (and is the way to fix Blood Witch to not be a downgrade with phys leech, Lifesprig, etc without 2nd ascend).

would it surprise you to learn that POE2's starting Life/Mana/ES balancing looks shockingly familiar to early POE1 balance issues?

Like they made the same basic mistakes (same as with many melee skills) and never learned the lessons from POE1, life being inferior to mana/es as a health pool describes probably half of POE1's decade after launch.

Anyone who tries to bring armour into it is just unaware of the situation. Plenty of Armour/ES nodes on the tree. at a guess I'd say you can get about 60-80% of the value a life only build can get while also getting more ES from those same nodes. Double dipping eHP.

Also in a game with better time til death than POE1 ES is stronger relative to POE1 ES. ES recharge is esentially a delayed flask that never runs out of charges and all you have to do is kite a little because in POE2 you get hit a LOT less often than POE1.

I would go so far as to say that even if you have almost the same ES as you have Life, and say 80% of the effective armour that ES comes out ahead as the MORE VALUABLE eHP pool in challenging content.

Now consider that you can have 5 times more ES than life, or if also scaling armour double the ES of life and still also have life.

ES is simply imbalanced, and the people defending it are the ones who are abusing it. They will change their mind quickly once they try to run the same content they steamroll on their Overpowered Shield builds on a Warrior HP build.