My one major complaint thus far is the lack of any kind of invulnerability window after getting smacked down because Nemesis is a dickhead and usually isn't kind enough to let you get back up most times. The 2nd form on the rooftop knocked me down into red 4 times in a row right after healing and getting back up before I was finally able to move far enough away to escape an attack and the chase sequence after he busts out the rockets I think is bugged because he usually stops firing and chases you down after the 2nd corner, knocking you to your knees and not letting you get back up or heal before finishing you. You can't outrun his punch in that part and I had no luck trying to perfect dodge it so I'm not sure how you're consistently supposed to clear that part.
It feels a lot harder than 2 was, that's for sure.