With respect - I find that 5000 watts is just fine.
I have run my whole house on a portable Honda 5000.
for ~ 30 hours in Canadian winter.
It runs about 8 hours on a gasoline fill-up.
It involves a bit of load-juggling, but nothing too difficult.
The well pump is run alone for 5-10 minutes - rest of the house off -
that is enough to run a good supply of water for drinking; washing;
After that - the rest of the house can be turned on
( forget electric stove ; clothes dryer ; water heater; AC )
My gas furnace; gas water heater; fridge; freezer; microwave;
sump pump; TV; computer; lights; etc - as long as they didn't try to
start-up at the same time - no problem. The furnace blower fan would
cause a momentary voltage-dip, when it kicked in - otherwise
everything was fairly happy.
My biggest complaint is the noise - conventional portable generators
run at 3600 rpm - screamers - Honda isn't the worst,
- but is still quite noisy.
The inverter models or the 1800 rpm models would be preferred -
- but quiet comes at a price.