We went to the RV Supershow in Tampa yesterday and all the 5th wheels we looked at had the island in the kitchen. We think that takes up too much floor space.
I also built our island it is 20 60 and 37 high, made from scrach it is on casters, we have oposing slides so we have the room for it. In the past we made other improvments, took out sofa, replaced the org. table and chaires. My wife would not be without the island.