Funny story, actually. I bought this thinking it was Starbound, and was horribly disappointing. I have no idea what build I was getting into.
What I got into was pretty much "build a base with a couple of buildings as a home-base, upgrade your characters and build armor and weapons, then kill the like 20 or so different enemies in the game."
I mean the way to progress your character was to get little data-chips that would increase your xp.
It was cute, but it took waaaay too long to progress, and when you did a lot of the time it felt like half of your progress was for very little.
Now it's been a while, there's a pretty clear line between enemies that act as a faction that alert each other and gang up on you(can get really tedious at times, but as long as this is a beta that's all good) whereas there's other wildlife enemies where some'll be more aggressive, but less factional in that they communicate with others of it kind, and then other creatures doesn't really care that much, but gets mad or scared if you attack them.
Base construction used to have a power generator and a command center's CPU-distribution as their main sources of power for the base equipment. Now they have Command Centers that power parts of bases, but command centers will conflict with each other, so you'll either have bases build into segments, or bases placed in completely different edges of the map, still connected by the Command Centers as one can teleport from one CC to another.
There's the separation between Phase-type weaponry (that doesn't use ammunition) that does less damage than projectile-based weaponry(which does use ammunition), there's signs that they'll end up giving us energy-based weaponry as well.
Game's also got a few vehicles, as of patch 0.4458 we have the Zephyr, decent hp, medium speed vehicle, pretty large, would guess about 6x7 blocks-size or so? There's also a Thunderbird, which I haven't tried, but it's supposed to be more armored, but slower. Other than these mechanical vehicles there's mounts: A crab, a jumpy raptor, a fast raptor and a net with captured jellyfish that works like a hoverbike. Jellyfishbikes have very little fuel, but are way faster than traveling by foot, never tried mounts as I was worried their lack of ability to fly or hover would make it hard to traverse in any useful terrain, as there's not much to gain by scouting the surface, unless you're on-foot killing enemies for loot and XP.
Hope to see the ability to equip and upgrade vehicles and/or mounts with different types of weapons/mining equipment in the future(choosing between phase, projectile and energy, potentially even one additional weapon slot in specific cases would add interesting layers into the vehicles section I think) Definitely hope to see refueling stations/refueling kits in the future as some vehicles are way to expensive to have them permanently expire after traveling a short distance, not to mention that giving the vehicle retrievability until it's destroyed could justify increasing costs of vehicles, and giving it said weapon/armor upgrades as mentioned earlier.
Not sure what the devs have in mind in terms of npc's or vending machines, but so far this game is intriguing.
The different AI behaviors are also interesting in terms of there being completely passive AI, passive-aggresive AI, faction aggressive AI's and some that will camouflage themselves rather than attack you for survival.
Nature yielding multiple resources as well giving different elements like sap, bark, the leaves and seeds, which affects what players can do in terms of crafting. It's half interesting due to different categories of crafting materials (Inorganic(processsed)/raw, minerals/chemicals/organic etc) but I also halfway feel like plants and gems end up kind of taking up a little bit much inventory space, as much as I adore the complexity. It works, but with a limited amount of inventory space it's definitely tough if you're going solo. Which also makes the swarmy enemy spawns a bit tough to deal with. Haven't tried playing with friends yet, so would say this'd be way more fun multiplayer.
All in all, in its current state I think that if you wish to roll solo and only go for weapons and armor upgrades I think the game'll last a few days. If you're going for exploration, building bases, upgrading yourself and essentially minmaxing on everything on your own it'll be worth everything from 1 week and up depending on how fast you are with these kinds of games and how much time you have to play it. I'm thinking 15+ hours a day being super efficient and lucky with weapon stats(Because weapons' stats are semi-RNG. Dmg per shot, in-game gun visuals, accuracy, crit rate, Ammo cap, MAYBE reloading time, and refire rate/rounds per second). Although it's a bit buggy and pretty slow in its current state, its simple "complexity" in crafting and although the devs(and their resources) are in charge of how much they can do with it I think it has sick potential, even if they end up sticking with the content they have right now, although more stuff's always beyond appreciated.
I'm very glad I stumbled across this game, and I hope it goes even further as this is awesome so far.
PS. Devs. PLEASE give me a way to change my looks. I'm stuck with a thing on my face that won't let me see the helmet-art.
Also, there's a bug where when you blow up a thing that explodes upon death with an exploding projectile, the explosion caused by the dying npc will destroy the projectile post-explosion and will cause a chain explosion in projectile and dead enemy, which nearly killed my application. If there was a way to fix that that would be great, meanwhile I'll make sure to only kill explosion upon death units with normal bullets.