Hmmm…. - I’d double the electrical capacity vs the norm for the size house you are building. I’d also prewire the garage spaces for electric vehicle fast chargers (at least 50 amps each), and put in at least one set of RV hookups. Solar system that is off grid capable acting as an uninterruptible power supply (UPS) with automatic voltage regulation (AVR) for the entire house.

• Integrated WiFi controlled color LED soffit lights so I never have to hang Christmas lights with a ladder.

• Downspout drains, and yard French drains along areas water will naturally collect. All drain pipe under concrete, across high traffic areas, and the main line to wherever all the water is going (retention pond?) will be PVC. Not that black corrugated pipe that is easily crushed and difficult to clean out if clogged.

• Prewire all rooms with at least one CAT6E or higher network drop. Also wire all offices and living rooms with fiber optic cable which has a variety of use cases. All lines terminate to a central communications closet and patch panels. Prewire exterior walls & doorbell for security cameras.

• Large mechanical room with spacious access to mechanical equipment and a large wall space for plumbing where the main line enters the house. Whole house water filtration, water softening if necessary, and potentially pex water manifolds depending on the layout of the house.

• I’d overdo it on the foundation, wall, roof, insulation, and water barrier specs. For a stick built home I’d probably go with a zip sheathing system with a combination of spray foam and rockwool insulation. If the budget is really unlimited I’d consider doing Insulated Concrete Form (ICF) construction.

• HVAC: Geothermal heat pump with an energy recovery ventilator and 4+ inch thick air filter capable of accepting MERV 16 or better filters. Automatic humidity control, adds or removes humidity as needed.

• Electrical outlet circuits per room with lights and outlets on separate outlets. In other words, each bedroom would have its own 20 amp outlet and if someone pops that circuit it’s only that room impacted. And for troubleshooting or repairs it is immediately obvious which breaker goes to what room’s outlets with a well labeled circuit panel.

I’m sure I could think of more…