The main issues with end game

So I have spent quite a lot of time on the endgame. Raised 3 chars to lvl 91+.
At the moment I can easily run t16 maps on corrupted/irradiated nodes.

There is no issue with losing maps on death - it's easy to sustain maps at the current state. The main issue I have with the current endgame is:
1) Exp loss is ridiculous. Either exp loss should be reduced/eliminated or they need to increase exp gain in maps. It feels horrible running T16(t18) maps and gaining no exp whatsoever. And lets be honest, with the rate T16 maps are obtained with corruption, we basically just run t15 maps with 0 exp gain most of the time. This is not fun.

all of my deaths are to white mobs one shotting me, when even the bosses cant do that... This aspect is also not fun. I would rather have boss fights more tense than having to avoid white mobs all the time. The game feels like you are breezing through mobs with no resistance, until one white mob one-shots you because the mob is invisible through some map clutter. If you reach the boss - you can relax, because boss hits for less damage than some random mobs on map.

The altars are not fun. If they spawn in some cramped corner where you cant avoid mobs + they spawn some tornadoes or hard to see purple pores - you are dead. Again + we could try and have a fun challenge here, but when it results in loosing 4 hours of exp farming - it just makes no sense to even try these game mechanics....

All in all exp loss on death should be mitigated in one way or another. We either need better exp gain in endgame maps (maybe higher tier maps with higher lvl mobs).

And the loot sucks honestly... Did a test run with 100% magic find for a week. Got zero interesting/valuable loot and only one divine orb. Considering that all my maps are juiced to the fullest - the current drop state feels unrewarding. The current endgame is designed only for nolifer players who can dedicate 24/7 to the grind...

I assume you mean map bosses. They are fine. Have to tried Arbiter? He can and does one shot you. You have about 1/10th of a sec. to move precisely or you die.