Raft 4

I played and enjoyed Astroneer, Space Engineers, and Raft, and Raft ends up being my favorite. Mind you, all of the games above «work» and are polished enough for me to invest dozen of hours into each.
Space Engineers is the most complex one and the building part is very nice once you get the hang of it, however, the game suffers from a lack of purpose. Yes, I can build all kinds of vehicles, even starships but why I should? After you build a tiny base to give you oxygen and energy any goal you have is one you gave yourself. It's the most «sandboxy» of the three.
Astroneer is the simplest of the 3 but I don't think this bad, and you eventually learn about the gates which give you a goal. I really like the interface and looks but the game is just too easy for its own good. After you realize you are 100% invincible inside a vehicle AND it refills your oxygen you pretty much found the game version of god mode, which kills the survival part of it and the game turn into a puzzle of how to open the gates in the most efficient way possible.
Raft end up working because it's the one that takes the longest for you to attain mastery of the elements. You need to deal with hunger, thirsty and the shark eating your ship and those keep being an issue for a good deal of the game which gives you a reason to explore the game in search of a more definite solution for those issues. The building is complex enough for you to make your dream ship, but not complicated enough for you to need a tutorial video explaining the physics of the game. I guess my biggest critics is I thought the girl character was a second dude until someone pointed otherwise.
I think what I want to say is, while there are several good survival games out there, the multiple moving parts of their system many times just don't align and Raft managed to be good simply by nailing the basics correctly. Quick example: Astroneer added automation to the game, which is fine but the simple stuff is easy to make manually, and for the complicated stuff like nanocarbon you only need a small handful. It's not automation was bad, it just not needed.
tl;dr - I enjoyed Raft. 10/10 would drink saltwater by mistake again.