Perhaps Mr Ford got it right when he said, "You can have any colour you like, as long as it,s black "
I dont see why the colour should be an issue ,but I would prefer something easy on the eye
Most of the old machines I ever saw were painted black, sure to get you off to a good start on a cold morning.
My own lathe is painted a sand colour, which is easy enough to live with, not so keen on those red or blue, or green ones..