I figured if I was aiming for color consistency, the old images had to go. Yes, I know they were fun, but the complete lack of professionalism was a problem. So, I created new ones. Below are the new page headers I made.
It is pretty easy to notice the consistent color pattern -- red, blue, black, and white. Or wait, is that light blue in one image and dark blue in another? Or is it purple? So much for consistent colors. I suppose I didn't do a horrible job for completely guessing at the colors when I made the various images, but they are clearly not the same. Considering the site still was attracting less than 100 visitors a day, I decided it wasn't a big deal and left the new images for a few months.