Nice to see you are getting a new garage/shop. Have to admit, I'm a bit jealous, I need one of my own, as the farm we moved to recently doesn't have a good space for vehicle repair and such, away from the barn animals.
I have a few comments on the electrical aspect, been in the trade for 25+ years. I can't quote NEC chapter and verse, but may look it up if needed. These are simply my thoughts and general practices, not 'hard and fast' rules, all subject to applicable NEC guidelines. And you may be in an area, as I am, where there is no inspection or authority having jurisdiction, and anything goes. Proceed with common sense!
PVC conduit inside... rule of thumb here has been to not do it. PVC when burnt puts off toxic fumes, so I've always avoided using it in homes, basements, structures inhabited by humans. Perhaps, in a garage situation, it may be acceptable, but I dont know for sure. Personally, I would use EMT and/or MC cable inside your garage, but no closer to the floor than 24". In a true mechanic shop, where gas fumes may be present, which settle to the floor, up to 24" can actually be considered a hazardous area, and requires explosion proof conduit and fittings.
Please take the time to run the actual ground wire in the EMT conduit. Required or not, it is your safety net, and you want that in top condition. All it takes is one loose fitting at a rusty box to open the ground continuity. I would also make sure you have GFI protection on all 120v outlets.
Grounding grounding grounding... I would put ground rods in for your new building, even if you're not putin in a full-blown electrical service (breaker panel, etc) and be sure the ground from the power supply and new ground rods/wire are bonded properly. And, always be sure to not tie grounds and neutral wires together anywhere past the power source where the main breaker is (AKA the 'service entrance equipment')
I may be repeating what others a have said, or you already know, but once I get on a train of thought, it all just comes out.
Enjoy your new building... I'm sure it will be nice to have the extra space.