Re: Fire in the stove burning out overnight.
Thermal mass and efficient fuel. You have a small stove, so increase it's thermal mass. Chunks of iron/steel, a pot full of rocks, anything AND EVERYTHING you add will benefit later both on the stove and near it.....heat the extra mass and inside of the bus to almost uncomfortable temps with cheap/inefficient fuel (wood etc), then gradually add fuel with more btu's per pound, but slower burn rate (charcoal, coal, VERY dense hardwood), Learn when to transition to this fuel based on bed-time...choke the stove down to slow the burn rate. The thermal mass will take over initially, allowing the fuel to burn later into the night and still hopefully keep things somewhat comfortable. Trouble is, you get "used " to the hotter temps pre-bed time, so later, when it is still warm, you may "sense" that it is cooler. If this doesn't work, prob time for either insulation or a bigger stove!!
Oh, and get a CO meter/alarm.........or you'll stay warm and cozy for a looooooooong time.