I can't find the pictures any more, but the best one I've ever seen was someone who matched the blue in the lightning on the cabinet. He also painted the scrolls that color as well. It looked amazing.
To me, the problem with the green is it blends in too much since the entire cabinet is green. The problem with purple is you either need to mach the purple on the cabinet, or the purple on the apron, but the two colors don't really go with each other.
The blue solved this problem as it matched the cabinet and that same color is used on the playfield.