What a great question. I have designed many spaces and I have to say it really comes down to practicality for me. Here are a few of my favorites. A second sink in the kitchen (full size if possible), an instant hot faucet at the main sink, magnetic door switches (light comes on when you open door, great for closets), a built-in dirty laundry bin in the closet or bathroom area, bedroom lights switched at bedside, a walk-in pantry, an in-drawer ironing board, a hand shower in all showers, valet rods in closets and finally, ample shoe storage. Let me know if I can provide any further information. Good luck with your new home. Charmean Neithart