A pretty mediocre map. I will point out the mistakes here.

So the first thing to notice is that the whole campaign is claustrophobic. Every room is cluttered with objects, furniture, and debris, you're in bad luck when a spitter comes in. The finale is too easy, with tons of boomer biles, I've managed to speedrun it. Now in terms of the difficulty, it's too easy. I played this on expert realism, and I barely took hits. I think I only took like 3 hits in the finale and that's about it.