Hiring someone to help unload the garage is a good idea. Much easier to insulate, wire, drywall when it's empty. And I agree, go with the fiberglass or similar insulation with paper backs. One weekend and it's in. Drywall is easy on walls, so's plywood of some sort. OSB is cheap and heavy as sin. Rent a drywall riser to do the ceiling. Save your back. LED hurts YOUR eyes, so get someting that works for you. Enough of the long standing joke. It's worn out and once you have it done, get going on the CNC. You have no idea how good you'll feel when you're up and running.
The more I do, the less I accomplish.