Finished on ultra violence (apart from the last boss, which I dropped down a level but don't tell anyone) and I thought it was great. There are some odd decisions in there which have already been mentioned but i'm not against repeating stuff.
The marauder is no fun to fight since it just seems to force you to clear out the room and then stare at it for a bit until it decides to attack. I was hoping it would behave more like the player, swapping weapons often, jumping about the place, being super fast. I was expecting it to be a fully fledged character based on the trailers too.
The purple goo. Literally just there to be annoying.
The UAC hologram. It wasn't funny the first time, never mind the 50th.
Tone wise I think they leaned too heavily into the meme of the doom guy. Doom 2016 was ludicrous but it played it straight, there's a bit too much winking at the camera involved in this one. I was laughing at his little office thing but probably not for the right reasons.
Other than that, good stuff, would play again.