Blank canvas, steel sided 40x60 pole barn. Thoughts on insulating, electrical, heating???

Another advantage of spray foam is mice don’t make nests in it. We had the shop at work spray foamed about 5 years ago and the mouse issue we use to have went away. The fact that it also eliminated any drafts in the building was a major plus. We did 4 inches On the walls and 6 in the ceilings.