Look at your power consumption to see where you stand on what your asking the battery to deliver.
There isn't a lot you can do about the frig or furnace, but look at operation s like fans (kitchen exhaust, fantastic, etc) TVs, Radios (
Look at Phantom loads (things that consume power, even when they ar not turned on. Radios, TVs, alarms,
Look at your lights, particularly if you have not upgraded to LEDs, each of your lights draws about 1.3 amps, BIG consumers.
Look at your converter, if its a single stage unit, you may want to consider upgrading it to a 3 (or 4) stage unit. These will allow a much higher charge voltage (quicker charging) This means a much faster re-charge of your battery from the generator or shore power.
2001 Coachmen Mirada (Ford F53 6.8L V10) - Toad 2001 Civic
It won't do MACH 2, but I can get a sandwich and take a pee.