Great feedback! If I had to resort to just using the car, my intent would be mainly heat, laundry capabilities and running a fridge. I do own a Kill-a-watt, I'll have to get it going and see what kind of power they draw. As I said, I know they are all energy star rated, but I'm sure the compressor for the fridge kicking on would be more than 800 watts unless my new fridge is significantly better than my old one. IIRC, the old one kicked up to around 1800 starting watts, and then dropped down to around 700 or so, so there'd be no way to use the fridge with any of them. Also, since the furnace is hardwired like usual, it's not like I can plug it into the inverter, so I would have to resort to a room space heater, which uses about 1300 watts while running.
Interesting idea on the high idle circuit...I don't know how easy it would be to do on a newer car that's not wired up for it. It might be easier to get a length of wood to wedge between the pedal and something else to keep the pedal depressed to a set rpm.