Things I recommend as an architect:
-Breakfast niche/appiance garage in the kitchen. Either a tambor door or pivot/pocketing doors on top of a countertop where you keep your toaster, coffee maker, blender and etc ready to go. Keep clutter/toaster crumbs hidden when you have people stop by. Clients love them.
-Lots of drawers instead of doors in the kitchen. If the kitchen is big enough, do enough drawers to eliminate upper cabinets above your counters. Sounds crazy, but everyone I've converted to this loves it, including me. Instead of uppers, give yourself a wall of full height pantry space, fridge, wall oven etc.
-A powder room. It's awesome to have a bathroom you know will always be clean when company arrives, with no medicine cabinet for them to look through.
-Large windows in the basement. Create large combined window wells (more than one window per well) if you don't have a walk-out lot. Doubles the space in a good way and takes care of any egress requirements. Can be terraced for planting so you're not looking at corrugated metal, block, etc.
-3 car garage... Mine is only 2 now, and I really, really miss the extra bay.
-Roxul mineral wool insulation. Fiberglass sucks... Roxul isn't that much more, is essentially fireproof, easy to install and better performing. We even use it in bedroom walls, floors and ceilings for sound insulation.
-Key/mail niche inside the entrance you use most. We file our mail as it comes in. Great for a place to set stuff down while first coming inside.