When I did my service upgrade the new main was in the garage and fed the house as a sub. That gave me access to plenty of power out there from the main.
I did leave the existing circuit in the garage that handles the overhead lighting and the door opener. That way, if I have someone snooping around in there I can put them in the dark from the house and keep the overhead door from opening.
Walking around in my garage in the dark could certainly get you hurt
