Any thoughts here on configuring the best bug out bike?

(or bugging in, as has been noted before, bikes would be priceless in some urban disaster scenarios in which roads are blocked by fallen trees or fuel is scarce.)

Do you start with a road bike? Mountain? Hybrid?

Frame preference? Steel?

I only have mountain bikes. Terrific for where I ride but the knobby tires would be slower on miles of pavement.

Pull a trailer? Panniers? Basket? Backpack?