Happy to help!
My thinking is faily simple with colours.. I simply cant afford to buy a box of paints and then hope one of them is going to be the right one.. So I always make sure that I have enough of each base colour and a few metallics, and I go from there.. I just find mixing myself on an old jar lid to be the best way to experiment and get what you truelly want.. The black with the metalic always gets compliments from my friends, as they say that it really does look like metal..
Anyways, thats the fun of modelling.. Always finding new ways of doing stuff.. I love it!
ps: If you are using Tamiya paints as I do .. Then when mixing a flat black with chrome silver, can get bloggy if over used.. The best thing I do, is to have my thinner ready, as I like to clean the brush a few times as I go.. If it dries too fast and you continue to paint over the one spot, it can lift, and you will get a grainy sandy effect with the paint.. Clean brush, and even strokes at a minimum, and you will get the finish you want!
Chris in Japan