- If you don't want to plumb for a full-blown water recirculation system ( to ensure instant hot water at spigots ), consider using something like the Auto-Circ pump. It installs under a sink ( preferably at the end of a plumbing run ) and plugs in to an outlet also under the sink.
- If you will have trees, try to design your roof so that the gutters have as few right angles as possible. Even with Gutter Helmet and the like, I suspect that if you have a lot of trees you will still get leaf build up ( perhaps not in the gutter ) on the roof due to leaves/pine needles/etc backing up in the corners.
- "Christmas circuit" ( or at least conveniently placed outlets for Christmas decorations ). These can include, but are not limited to, plenty of outdoor outlets, outlets in the eaves for roofline/gutter lighting, outlets under windows ( indoors ) for those candle lights, outlets up in any nooks or shelves where you might consider putting a small tree or Christmas lights.
- If you think you might build an outbuilding in the future, run some conduit to that location to make it easier to pull wire for power to the building.
- "Ufer" ground. I don't how common this is, but from what I understand ( I am far from an expert ), this can provide superior grounding for your electrical system than ground rods. At its most basic level, the rebar in the slab/foundation is tied into the grounding system. You can probably find out more by searching this group for "Ufer".
- Quiet bathroom fans. Panasonic makes a very quiet one. Remote mounted fans ( such as Fantech ) are also a good choice.
- Radiant heating under tile in bathroom, especially if over an unheated space on directly on slab. This heating does not necessarily have to provide all heat for the bathroom, but it is nice for taking the coldness out of the floor. Electrical products are available.