Directories Color Coding

Is there a way to either import or change the default color presets for color coding buttons in directories? I like to color code my groups and pallettes based on fixture type (shades of blue for spots, shades of pink for washes, red for beams, etc etc) and I'd love to be able to adjust the default colors you see when you color a directory button.

At the very least, the ability to input a hex code into the custom area would be awesome.