My parents shop was built by Mark Strait of Straitline Structures. It's an all steel 60x100 20' at the eves with 3 18' tall overhead doors and 2 walk in doors. 80' radiant heater running down the middle of the shop.
As far as electric, there is a 4 outlet box for 110 every 20 feet. There are 4 220 boxes in the middle of the walls. My welder extension cord is 50 feet so I can reach any spot in the shop. There is a room built with heat inside that has a few arcade games, fridge/freezer, stereo, pool table, and my reloading bench. Over that room is a loft for storage and random junk.
Things you may want to consider:
-Decide what size you like, then go with the next size bigger. My parents had another pole barn built within 5 years.
-Have drains placed just inside every overhead door and have the concrete sloped more than standard sloping.
-Skylights