Not trying to through a wrench into anything...... but. What would it take to have a plug installed to your electric panel, so that you can back feed a generator into your panel. Enough to run the necessities. Fridge, freezer, furnace, and couple lights through the house?
As far as the furnace going out being a problem. Pellet stove, you could cut your gas bill substantially with that running regularly anyways. Just some food for thought.