There's probably one thing I'd do differently and that would be to add some form of protection around the exposed lamps. What shape that would take depends on the application - what you would build for touring is different to say a wire guard for an installed application...
PRG built something similar many years ago to test their touring racks in the shop. They had 96 100w A lamps mounted on a big board each with a big number written on the bulb to correlate with the circuit/dimmer #. They had 16 6cir Soca cables connecting the test rig to the racks for easy hookup.
Low tech and works great!