I'm not related to the project. I shared a cool link I found online. But I can think of at least two improvements over using regular colors. The first one being better support for people with color blindness when using a large amount of categories. And the second one is the possibility of showing more than one value at each sector. Something like http://i.imgur.com/SdLeAPa.png shows combination of two kind of data. One being the light/dark background, and the other being the circle/dash pattern