This game took me entirely by surprise. I admit when I bought it I was expecting a pared-down 3D imitation of Unreal World, as I intentionally went in without knowing much about the game. Instead it's something very different that, for some reason, really draws me in and makes me want to play more.
The aesthetic took a bit of getting used to but actually looks beautiful, as long as you don't isolate any one object up close, and the soundtrack is gorgeous and really helps set the tone. Between the runestones and tutorial-duck's hints you have enough information to give you some direction without holding your hand too much, and is cryptic enough to encourage you to explore and experiment.
I didn't know what the death penalty was so there was some real tension when I've been in danger; I bumbled my way into the black forest, ignored Odin's prized pigeon's warning, and ended up having to run away from skeletons and cantankerous dwarves. The Eikthyr fight was a massive change of pace from the rest of the game up to that point, too (and I was not expecting that musical score). I survived both encounters, then later died to a tree falling on me. Because of course I did.
I think the thing that separates Valheim from some of the other survival-like games like Ark is that you feel like you're inhabiting the world and are a part of it, not just existing in it. I can't pin down exactly why that is, but there's definitely a feeling you don't get in many other games when you're drifting down the river in your raft or running through the meadows looking for deer.
Massive props to the developers, this is far more polished and enjoyable than I expected for the price, and it really doesn't feel very early-access so far.