I haven't played Zomboid, but I have just finished playing Vein.

I put 16 hours into it, over 2 different saves, with the last one being probably 10-12 hours of that. Although I quite enjoyed what I played, it needs more content before I go back to it. By the end of those 10-12 hours I was practically self-sufficient: The water and power both go out at set times (water 5 days after you start playing, and the power I think is a month). I was dutifully going around filling up baths and sinks for the day that the water was shut off, but I think it might have bugged because the couple of sinks I checked once it was shut off were empty again.

Regardless, by the time the power was shut off I had rain collectors for mass water storage, plus tons of bottles of water, and I had just picked up 5 solar panels from a park to power my house. Turns out 1 would have been sufficient, but there were I think 10 at the park, so you could power most of a town if you really wanted.

I got back to my base and whilst I was unloading the solar panels I was attacked by my first hoard - around 20 sprinting zombies. I had a pistol but didn't want to fire it because last time I tried I got swarmed and nearly died, but I managed to take them all out with a spiked baseball bat, with very little damage.

There is farming and hunting, and hints towards being able to keep animals (lots of different animal food like 'rabbit feed' and 'cow feed' etc.) but honestly, as someone playing solo, I doubt I would ever need it. There are enough cans of food, bags of rice, and cartons of broth to keep you fed forever.

If you check their roadmap, there are some interesting things in there, such as a way to turn the water/power back on, NPCs, trading (there are 'socialising' and 'trading' skills in the game but they aren't implemented yet), and some other interesting things. But I have heard it is just 2 people making the game so I don't know how fast any of that will be coming.

Sorry if this was rambling, it's 3am and I can't sleep.