Oxygen Not Included is a space-colony simulation game. Deep inside an alien space rock your industrious crew will need to master science, overcome strange new lifeforms, and harness incredible space tech to survive, and possibly, thrive.
Oxygen Not Included is on sale this weekend. If (like me) you happen to have wanted to play it for a long time, but were worried you lack the patience/stamina and give up after a couple of hours, the price is now at a level where buyer's regret is rather unlikely.
Even if you you don't want to plough 1000 hours into it I still think you'd get a lot of enjoyment out of exploring the game for a normal 20 hours or so, it'd definitely hold attention longer than that even for the most impatient player. It just has so much character and pull to move up the tech tree and make cool layouts.
I love ONI and Don't Starve is hard for me to get into. ONI is a mechanical/technical base/management simulator. I'm a huge Factorio player and ONI scratches a pretty similar itch
I don't know Don't Starve and have only played ONI for a short while, so the other answers are probably more helpful that mine, but at its core the game is about managing (and obtaining) limited resources. You start out inside an asteroid with a limited amount of oxygen and food and need to build a sustainable environment from there.
Silly fun also seems to be a big part of the game - one of the character stats (they're called duplicants in the game) is the reaction to stress, and apparently one of mine is an 'ugly crier' and another one a 'binge eater'. Two appear to have a crush on each other and spend the day avoiding work and exchanging heart symbols whenever I'm not watching.
As for the game itself - yes, I find it very overwhelming. There are short tutorials on how to navigate the map etc. and a lot of stats, but not an awful lot of info on strategy or what exactly is expected of you. So far it's still fun though.