My shop is 60' x 100' with the front half finished and heated. Some years ago I installed an overhead radiant tube heater like this one.
https://www.reverberray.com/?product=des3-series
Heating costs went down substantially compared to hot forced air system I had previously. We are on propane so I couldn't speak to natural gas costs.
Friends water for radiant heat is powered by an outdoor wood furnace. He, his Dad and Uncle are farmers with substantial woodland and time to cut it with equipment to handle it.
Me, I haven't cut wood for heat in 30 years and the propane heat works for me.
My shop doesn't have floor drains and they would be handy....though we've survived well without them in the building since 1968.
Another friends shop is 60' x 50' and he doesn't have floor drains. Instead his floor slopes toward the doors much like a home garage. Handy for run off and not so handy for levelling and installing a chassis clip on a hot rod build.
So, for heat and drains, what will work best for your use of the building?
And water in the building would be real useful. I don't have it and that is one item on our gotta do list.
Sorry so long of a post.