Allan,

Looks like the world is your oyster on colours!.

As you've already had a metallic & a solid colour, perhaps a special effects paint might be next (such as a pearl).

I've always personally felt that black is the most timeless colour, but - whilst it looks great done well, when clean on a very straight car; it has the same as downfalls (ie. shows up all dirt & dust, highlights any body imperfections).

Good Luck on the colour hunt!.