[Three Peaks]

How large are the individual rooms? That will determine a lot about what type and size of heaters you will need for the space to be heated.

I just reread your post and realize you have a single room. A room this size will require probably 2 unit heaters hung from the ceiling with fans in them to circulate the heated air. They would need to be pointed so they create air movement around the perimeter of the room, so one fan pointed down a wall clockwise fashion and the other heater in the opposite corner pointed in the same clockwise direction. A good thermostat will control them but with 2 heaters at 230V- 30 Amps you will need the Thermostats to control a contactor to turn them on and off. Separate Thermostats can be used but they won't be as precise for control. You would need to place the Stat in the middle of the room between the two heaters probably on the wall where you have the most heat loss- probably at the doors.
I install these heaters quite often for customers and they are fairly efficient and will heat a room very quickly. I'm an electrical contractor. Just be sure you have enough Electrical power to run all your planned equipment and these two heaters. If it were me, a shop this size would have it's own Electrical panel and possibly a separate metered service rated at least 150 Amps/240 volts.

I would put the compressor in the upper floor just to avoid the noise, but you will still need additional water traps in the line. I've heard about every 50 feet of line needs a trap, plus at least one at a spray gun if you are painting.

Bob