[Aaron]

You could do that as an array of choices on the background (1-6 and one more for choose your own), or you could just have the background show a user text field next to the name. The most complicated way (not sure if you'd think it was important enough to do this), would be to have the background bootstrap what is called a Configurable, which creates its own tab with tables based on how you set it up. You could then create each of those 6 schemes (or more!) and associate them with the Configurable you created.

Edit: Err, just remembered that backgrounds don't show as a pick in a table, so the Array/text field option would have to be through a bootstrapped racial special instead.