We're doing the Snowbird thing for the first time this year, too. We'll have a plumber winterize the house because the pressure tank and water softener live in an unheated room; and then we'll keep the heat at 50 degrees, because I don't want to have to chase down everything that could be affected (like paint and other liquids) by freezing temps. We also have a tongue-and-groove wood ceiling - I'm not sure I want to subject that to freezing temps if I don't have to. Even if we lose power, the house should be fine for a few days. I have temps and security monitoring via internet - I can send my son over to check any problems.
To help hold heat inside, I put window film up, then draw the blinds