I bought this for the building really. You mostly go around and find stuff, kill stuff, and build stuff. The progression lies mostly in the caves where you find most of the weapons and equipment, which then help you to more easily find stuff, kill stuff, and build stuff. There is a backstory to be found in a series of documents and other evedence.
I played the old game for a long time, since the early early alpha days. This is a pretty good follow up to that from what I've seen so far. Base building is quite different, and for the most part better. It's a little restrictive in terms of load bearing support, but the emphasis is on realism rather than flexibility. The graphics have improved significantly, although I occasionally get random periods of poor FPS for no apparent reason. On a 10700K CPU and 3070 8GB GPU running 1080p I can get 60+ FPS with ultra settings most of the time..but not all of the time. It's pretty annoying when the micro-stutter starts. FPS also seems to drop during certain animations, like opening the inventory and cutting down trees.
Are there bugs? Yes. Quite a few. I see purple error spam in the dedicated server console often. Some items don't seem to work properly, like the cross light and leg lamp. Sometimes there's building glitches that require a game client or server restart to resolve. I got knocked back while also opening a trap door the other day and ended up climbing down an invisible ladder right into THE VOID. I also just got my first crash-to-desktop a little bit ago. I hope that it's still in development, because many things still need improving.
It's unfortunate that there is not a Linux version of the dedicated server. Yes, probably most average players would probably want to run it on Windows, but I would prefer to run it natively on a real server OS that isn't trying to also run a desktop full of data mining BS in the background. I've read guides that suggest using WINE to run the server on Linux. That's a pretty sleazy way to do it though.
There's also an attention to detail in this game that you don't often see in other games. Take the wall clock for example. Sure, it's made from sticks, a battery, wires, and a couple cannibal arms, but one of those arms is wearing a wristwatch and that wristwatch is also telling the correct in-game time. You should also take a good look at the stars. In most games with stars you're just looking at a bunch of little random dots. I'm not an astronomer, but I can spot Orion's belt pretty easily. I'm assuming that it's not just the Orion constellation, but the whole universe that is accurately mapped in this game.
And of course there's Kelvin. My very first attempt at playing resulted in the death of kelvin. Little did I know at the time how useful he was. Even after restarting the game to get a new Kelvin, I failed to really look at his abilities until after I had built a shelter. Kelvin can do almost anything, except it seems, cross though a defensive wall gate all by himself. He can however collect materials, repair or help build your base, collect fish, reset traps, and even find all those arrows you thought you lost.
Even though I have some complaints, there are many good things that can be said. I would recommend this game if you enjoy open-world survival games.