Floor drain?
It's a lot cheaper and easier to rough in the electrical before you insulate. Are those scissor trusses 4/12-2/12? I put a Beacon Morris 75,000 btu vented propane heater in my shop. $400 at Menards. 500 gallon outside tank. You have a sharp looking building. If there are two things I am sure of, you can never make the shop too big and those little trees grow up to be big trees and they do have a habit of falling over. I know. I lost well over 200 last summer/fall $.02
Nice thread, first time I saw it.