Good post, you certainly are experienced!
For the typical person though, like me, I would be leary of propane IF I didnt have a 120Lb tank because we dont get power outages and the generator would sit for years unused. Until the once or POSSIBLY twice every ten years hurricane smacks the area, then it could be a while for power to be restored.
Being it would be so rarely used I would only buy one and I know it would be running more than 50% load so that tank can be dead in 12 or less hours. Again, I have a 120lb tank though. IT wouldnt be possible to buy and store 20lb tanks, though I have one for the grill, but in my HOA community regulations are tight.
Agree, I run Magnetic plugs in everything I own.