I'm planning to do a dark blue paint on my build, it's a BMW color, Interlagos Blue Mica.
I too have been torn on what to do with colors but have settled on a two tone, red/black, interior, also taken from BMW. Here are a few pics, though the red doesn't show it's true colors it gives a good idea. As mentioned, I think the key is to get some black in there, though maybe a graphite could work just the same. These pics were taken at BMW in Germany of a car in the same color blue as above.
