Electrical Code
cadman, I don't want to come off sounding overbearing and humorless, but I do hope you will think better of your cavalier know-it-all attitude regarding electrical codes and safety.
As difficult as it may be to imagine, the National Electrical Code is not written by a bunch of frumpy busybodies obsessed with minding your business, stifling your creativity, and ruining your fun. Every rule in the NEC, no matter how arcane and incomprehensible it may seem to you, is there for a reason, and they are mostly good reasons. Behind rules governing grounding of circuits, GFCIs, proper overcurrent protection, and minimum number and rating of circuits (among other things), there is a long-buried litany of tragic tales of electrocutions and fires which are now very rare as a result of the rules you so carelessly disparage.
You should hear the language I use when faced with the need to correct really bad DIY wiring, when almost any amateur could do a halfway decent job by reading and applying the directions in a good DIY book (not all of them are good). I've found that engineers, electronics technicians, auto mechanics, etc. are often among the worst offenders. A little knowledge can be dangerous!
Re: three-prong outlets
These were readily available in the '50s, albeit infrequently installed. They really don't detract that much from a '50s look, and if you really don't want to see them, you can mount them on the underside of a wall cabinet. Outlets in living rooms/bedrooms are usually hidden behind furniture anyway, so there they are not a concern. If you absolutely must use non-grounding outlets, at least splice the ground wires of the romex together (don't snip them off), and bond them to the boxes (if you are using steel boxes). That way, a future owner can undo your creative anachronism without undue expense.
Incidentally, it is not necessarily true that two-prong outlets are safe if you are only using appliances with two-prong plugs. Lots of vintage appliances could stand to be made safer with the addition of proper grounding. My vintage fans all have the most retro-looking grounding cords and plugs I can find (the originals are in a drawer, labeled for the appliances they match). Don't ground toasters or anything else with exposed ni-chrome elements. It should go without saying that an appliance with a two-prong plug isn't safe if the plug only has two prongs because you snipped the ground off!
30-amp circuits:
No, please, no!!
Many houses have burned down because of this. Use 20A circuits (with #12 wire), and lots of them. Two in the kitchen, with built-in appliances and refrigerators on their own circuits, and no lights on the circuits is plenty for most houses. If you want you can have four or five. This is much safer than 30A circuits.
GFCIs:
GFCI circuit breakers are available, so you can have GFCI protection in areas where it is a good idea (and a code requirement, not that you care about that) without looking at an offensively modern outlet. Required locations are bathrooms, kitchen countertops, garages, basements, and outdoors. They are not recommended for refrigerators/freezers, computers, or life-support equipment.
I have a 1930 book that recommends grounding washers and explains ways to do it. This was known to be a serious safety issue for many years before the Code actually did anything about it.
Your retro house plan sounds lovely, and I can't wait to see the turquoise appliances. The low-voltage switching is a cool idea, too. The parts are hard to find nowadays, but they are out there. Don't get me wrong; I'm not against creativity and I love retro (otherwise why would I visit this site), but please consider those who will inherit your handiwork. That's all.
