if it was mine to build,...
big doors tall and wide.
max ceiling height.
pitch the floor out not to a drain.
either trusses or a steel beam so there would be no lally columns.
if trusses still some kind of heavy beam for lifting.
put radiant in the floor even if you cant afford to hook it up now.
large cement apron in front with more radiant, no shoveling in front of doors.
max electric service for welders, big compressor, a/c, etc.
piping for remote compressor air usage.
max outlets 110v and 220v.
lots and lots of lights, nothing is worse than too little light.
plumbing roughs for future hot and cold water, bathrooms, dog wash station, etc.
separate walk in door less heat loss than thru the overheads.
fire code sheet rock even if its not required, welding sparks etc.
if its going to have live water in it overhead sprinklers are real cheap.
secure locks, dead bolts.
no windows, not even on the doors.
thats just off the top of my head, seen to many regrets from homeowners after the fact.
woulda, coulda, shoulda, gets real expensive after the fact.
this list brought to by caffine,... and 30 plus years in new construction.