Thank you! I guessed that you'd like the header graphic when I was doing it, for some reason I was thinking it would appeal to you somehow. Don't ask me why I was thinking that, but it is rather off that you were the first to comment!
I have a thing with that kind of symmetry, it's an extension of my fanaticism with harmony that borders on obsessive compulsive. Most of it comes from sampling colors in a random pattern like the one produced by the concrete picture, which was heavily adulterated. I kept sampling until I found the five I eventually decided on, and made a colorbar with them. That's the best way for me to see how they're going to work together. If it strikes me as seamless, then I know I'm on to something. Once day we'll sit down with Photoshop and you can get a better idea of where I'm coming from.