The just-in-time hot water heater and the Washer-dryer is the problem.. Usually these are huge power sinks typically 7-12KW for the hot water heater and 2-3KW for the washer dryer. So I'm assuming a 20-30KW gen set installation. With such a large gen set just turning over it will consume the propane quite readily without any load.

A much smaller Gen set to cover just electronic and lighting base load will probably be just 300-500W

Energy efficient devices are the way to go;

LED lightbulb 3-10W - Typically a 3 bedroom house - 150W max

Freezer - 30W

Fridge - 15W

TV 80W (can be a huge difference in power draw if you turn down the backlight i.e. 80W for a 40 inch Flat Panel to 200W on full brightness.)

Hi-Fi - 20W

Computer desktop (PC) - 30W + Monitor - 25W

Modem/Router - 15W

Boiling water and cooking can be provided by the direct use of the propane within the propane tank itself. Converting propane gas to electricity is around 25-30% efficient using a generator at the rated maximum load for the generator. It doesn't make sense to then convert the electricity into hot water at 40-60% i.e. if using an electric hot plate cooker ring. The energy in the propane to heat hot water this way would then be about 10-15% efficient. Using a kettle with a heat exchanger base such as Simplex No4 kettle over a propane ring is 80% efficient i.e. will use 1/5 less propane fuel.

For washing clothes a mangle and a clothes line might prove to be useful. It also keeps the ladies a little fitter as well...