I think the whole process is entirely normal

-Valheim blew up
-Development had to shift to stabilize the rapid player base and offer bug fixes
-They had full intentions of making bosses for each zone and fleshing out each zone to begin with, which is why those zones existed in the first place
-Early Access players offer feedback and suggestions
(this goes back into development)
-Updates are not as fast because it's an Early Access game. Basically, you are paying to play a version of the game that's essentially what would otherwise be a playable version of the game at the Development studio. You won't get paid to "play" the game and test it, but you will get a discount on a regular game debut price, and you only need to offer feedback. You do not have to lend your time to working on the game.

Essentially it's a bargain that some studios do when they make essentially an indie game where they're unsure if it's desirable before more development is made.

I've gotten all my money's worth out of it...especially when playing co-op