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.
It's a short game.
And it's easier once you know some of the "secrets", like where to find certain modules, where the various paths are to the lower levels, etc.
But, why would you replay it? I actually like both the original and sub-zero, but I didn't replay them.
I started doing challenge runs of Subnautica. I enjoyed playing it, so I tried some different play styles. Then started making a pretense at speedrunning it. My PB is 3:56.