The Other Half
Gold is the traditional colour. Works well with red and white. Although funnily enough, I'm thinking of changing my centres to silver as it'll suit the lemon/lime better. Thoughts? I've seen a snow white with black centres Simmons. In my opinion, they get lost and don't really work. Gold would work well for snow white :)
I actually think the gold centres look quite good on your car Nathan... and your car is looking very shmick in general.

Black centres would also work well with yellow but as you say, the detail of the centres gets lost unless under direct light. Not sure about the silver with yellow... I would probably stick with gold, but thats just me.