I love me some Valheim in the same ways already mentioned. Sense of progression. Little details even with old school PS3 graphics. I like the random rain storms and the way the ocean works. Fog at sunrise. Red sunsets.
I haven't visited Mistlands yet. Holding off judgement until I visit. Every new biome feels like a spike in difficulty so I'll expect the worst when going in and prepare as best I can. Started a new seed and building up again.
My big goal is always to build the perfect base, in the perfect spot. I've yet to do that but the building is fun for me. Being able to shape the terrain and level a forest and even replant it is a cool mechanic.
Because I play solo, I also use Valheim Plus and some other mods to make the grind and difficulty suit my tastes. It is great having that option.