How about a full working dairy farm? And if the villagers grew wheat and potatoes as well, they could open up their own McDonalds and serve cheeseburgers and fries which would make a change from vegetables, coconuts and fish. I am a bit concerned about the low-carb diet the vilagers are following!
(Of course, all this would have to be after an Island Event in which a bottle of cola was washed up onto the shore...)