To spice the game up a bit more and make it feel more interesting, there should be random events which happen daily and weekly, a long list of events with different effects.
Some examples:
Big storm (Travels across a certain area of the map and is like a hurricane)
Grounded Spanish treasure galleon (first person to find it, gets the loot)
Economical changes.
Increase / decrease in Pirates in certain regions of the game.
And more :-D