I've been revisiting anno 2205, infamously the ugly duckling of the Anno series of RTS games. I don't mind so much the fact that it's different, lacks customisation and random map generation - I'm bothered because the game is so slow to progress through on challenge settings, and it feels like a game designed just to artificially waste your time; in other anno games, you can always pull tricks to dig yourself out of economic crisis - selling off assets and surplus goods, completing quests for other parties, or taking loans. 2205 is very very confined in terms of what you can do to financially recover in the early game and forces you into a lot of military events.
I had gotten Subnautica free with PlayStation network, so was quite happy to pay for Below Zero when it came out.
Played it until I was forced back on land, and gave up.
Recently I went back to give it another try, and played it permadeath.
There were a handful of moments that reminded me of why I love the original, but not many.
Like you said, way too many tight winding maze areas that all felt very the same. It traded wide open depths for claustrophobia.
I really am looking forward to 2, I don't have a PC so will have to wait. Trying real hard to avoid spoilers.
I have played 2 in EA. So far they've gotten the artwork right, it looks like a Subnautica game should. It's mechanically similar, swimming feels right although a bit slower. The story...let's just say it makes it look like Riley had it easy.
I'm not convinced BZ's on-land setpieces aren't just broken.