Also using characters only go so far, the other boards wouldn't have a graphic if that's the only guideline so something needs to be decided for the rest of the boards if you really want all of them to have some sort of uniformity. Random anime renders would not only save the time of rendering, but they'd be a style match for instance for the art forum find some sort of anime painter though with as small as the board images actually are getting enough detail to show that might be an issue.