I'm loving these, and I say this as someone who's just unlocked them yesterday and ate dookie in the msq level 100 final boss because I wasn't expecting them to layer 3 things at once. It's awesome.
I've also really loved how they use the trash mobs as a way to foreshadow boss mechanics. Like in the msq dungeon with the holo walls, they foreshadow fake walls on your way to the boss and then fake walls are part of the fight. The content has been the highlight of this expansion, which is a good thing because it's the content we'll be repeating the most. Whoever designed these, give them a raise and keep them on staff please. Even after you "get used to" the mechanics, you still have to perform them which is a lot more than I can say about the slop we got in endwalker.