When I had a 2 bedroom cabin, heat was small fireplace and baseboard electric heat. No propane used. If you have AC, it's the way to go in winter. Propane would be the backup. That torpedo looking tank is probably 100 lb by the way. Their fun to move around. You'll get good at rolling it on the bottom edge then lifting it into vehicle for refill. Way better than messing with 20 pounders during winter.
We use a Honda EU2000I generator at the fish house. This is an 8 hole large house setup like an RV. Look up Ice Castle for simular model to what my buddy has. Anyway, they have propane furnace, oven/stove, 120volt lighting, etc. The generator runs for 5 hours or so on a tank, easy refill, and works great at sub zero temps. Honda EU2000i Super Quiet Generator
Electric blankets on the bunks keep us toasty so you don't have to run furnace so much.