A good friend of mine was an advocate of 1:64 scale. He had some wonderful brass stuff, and even had some cars designed and manufactured (Chesapeake Models, if I recall). Sadly he passed away before the internet was really a platform for the convening of fringe elements (like S scalers) and I can only imagine what he would have done with 3D printing... I've always thought it was a good scale, and like early N, requires a lot of modeling because of the limited offerings of commercial stuff.
Lee