OP here:
When not in use, the small generator will have its main home in a plastic tub in the basement storage compartment.
When I'm boondocking and running the A/C, the Onan does the heavy lifting, powering the inverter/converter (which I will be replacing with a Magnum Energy MSH-3012M model, so a Texas brownout doesn't fry my A/C unit.)
However, come winter, where I'm not needing 2017 watts being pumped from the genset to the A/C so my rig is habitable in the Texas summer, the Onan is a relatively thirsty beast, using 0.3 gallons an hour just to spin its crankshaft at 3600 RPM. I can run a Honda eu1000i for 2-4 hours on that much fuel, and a smaller generator even longer, especially if it is an inverter model that can run at lower RPMs. I also can use a separate battery charger to reduce the amount of amperage required.
Definitely, solar will help. However, it doesn't hurt to have a spare, small generator, just so the generator can be placed well away from the campsite when boondocking.
