You just were unlucky. You probably passed a Greydwarf nest, then next a burial site. You can't just storm through this world. You have to take it slowly. That you had three events in a row is just bad luck. I had in game weeks of no events. It's totally random.

I think it's the right mixture. Some people complain there are not enough mobs (especially plains). I find it just enough. Any more and it would ruin it for me. On that one largish Plains island I've been spending my time on lately were tons of tar pits! You had to watch out were you were going, or you had one of those growths at your heels.

That was almost too much for me as well. But I learned to live with it and proceed even more with caution. Which is what you should do in Valheim.