@dcook The color you want to change is not property of the categories, but rather the property of the theme. Black is the theme color for section categories (non-clickable link) and blue is the theme color for non-section/normal categories (clickable link).
That's why there is no option to customize it on categories management.
I have to say that programmatically being able to show and hide content in a widget is fabulous. I now have a Global > Global Header widget that displays an image and text only when it is the "home" page.