Here are my suggestions:
1) larger map area - particularly on the east-west axis. My very first experience after building a ship was that I'd reached the map boundary. That was very discouraging. I did manage to find other Ylands, but it didn't take long.
2) More structures and greater variety - the structures we discover are cool, but repetitive. More of them, and more kinds of random structures would add richness to the world.
3) More threats -...
