Sir, you are much more than a weekend hack--that is beautiful work. I never thought of mixing different sizes of flake. I now have the confidence to give it a shot through my primer gun on a few test panels--what do I have to loose, LOL.
That's what I did, I like to use silver sealer as a base then lots and lots of flake!
I wont consider myself a weekender hack when I stop sanding off more than I keep!