Second no integrated appliances. They are expensive and harder to replace because the cupboards are designed around them.
Make sure you have plenty of plugs fitted above the worktops. Lots more gadgets these days.
Don't have an island for the sake of having an island. Only have one if you have plenty of space.
Don't get mdf vinyl wrapped doors. They swell up and get water damage. Solid wood lasts a lot longer.
Check your kitchen has wiring for high demand cooker, or fit this if you are having it rewired.
Plenty of extraction capability to get rid of humidity. You want that out the house.
Think about how you are actually going to use the kitchen. So if you take something hot and heavy out the cooker, where are you going to put it ? Carrying a heavy red hot roasting tin accross a room bad idea.
Make sure you get spares for everything so when something gets damaged you can replace it.
Make sure your storage is near the dishwasher so you can take stuff easily out and into the cupboards.