What stage is the house in?
If you haven't started the foundation yet, you may want to redesign the kitchen. Do it now so you won't regret it later.
What is your kitchen triangle like? Where is the breakfast nook in correlation to the kitchen? What are your needs? What appliances do you want in the kitchen? Any "luxury" items like built in micro or the drawer? Point of use refrigeration or a beverage center? Seperate refrigeration units (freezer and fridge) or one single unit? Warming drawer or no?
The kitchen island that replaces a breakfast area should be quite large in size with seating away from the working triangle. Preferrably, seating should be outside the kitchen prep zones.