It would be nice if we could configure our game with worlds that are based on questions you answer like :

How Many Islands?
1st Boss to be on Spawn Island?
All Bosses to be on Spawn Island? Which would make that island bigger from other islands.
Bosses to be on seperate islands?
Size of Spawn Island (Main Island)?
Size of Other islands not Spawn island?
Trader on Spawn island?
# of Random Buildings on Spawn island?
# of Random Buildings on Other islands?

This would be the best balanced system instead of complete randomness and we know the sense of the islands, you don't know whats on the islands (other than bosses) but its still a true exploration aspect.