Originally posted by Woundstring:

I've crossed an ocean and been on about 4 islands i think, Are the other Biomes rare in comparison to Meadows & Black Forest?

The middle of the map is dominated by meadows and black forest with mountains sprinked in.

You have to move further if you want to find other biomes.

https://valheim-map.world

Generate a few random maps to get a feel for the dimensions.