This really wasn't that hard, guys. I played through this right after my first playthrough of the base game, both on Ultra-Violence and it's really not that much harder than the base game. Got through the first two levels without a single death, and only died to the final boss on the last level because I got too careless. So many of the negative Steam reviews are so obviously just people having a skill issue that it's hilarious, they're a good read.
A definite recommend for any fan of Doom Eternal who wants a bit of extra challenge.