building pole barns in the sky

I have a 44x40 pole barn here are my regrets, Should of had them spray insulate it, I have the walls insulated now and some particle boards on the walls. PIA to install, also think about under floor heat and a sink. I have 16' ceilings so height is not a issue, one more thing if you plan on putting a lift in have them pour 6" concrete in that area. Paint the floor also before moving anything in, that is the time to do it. Outlets also cant have enough and if you weld 220 is nice to have. Just my experience of what I should have done.