I've been playing through Doom 2016 again in anticipation of Eternal. I like the game, but man, there is so much room for improvement. One thing that really bugs me is the aesthetics. The original Doom wasn't afraid to use some bright, vibrant colors. Playing 2016 today, I had to laugh when I came back to Mars and for an entire level my screen was just different shades of red. It makes everything look flat and boring. Give me some contrasting colors!
Aside from that, the whole "lock you in a room and spawn in demons" formula is kind of weak. I actually enjoy those sections because the combat is so satisfying, but I would prefer more instances of enemies naturally populating the map. I'm guessing that this is for performance reasons, though.
I actually haven't watched anything on Eternal, because I don't want to spoil the experience. So, I'm just hoping they improve on 2016, but since it was basically universally praised, I'm expecting more of the same, for better or worse.