Previously I mentioned using the 0-9 keys as a r'ating system' (for the background and style, separately), with a '0' essentially the same as unchecking a selection box in the Configure window.

Perhaps an even better method would be to simply use SHIFT+UP/DOWN_ARROW key-press combo for boosting/suppressing the "rating/ranking/popularity" of a style, and the SHIFT+LEFT/RIGHT_ARROW for the background.

That way, there is no assigned number a user would have to remember relative to another -- the number of "votes" for-against a display as it appears (i.e., the actual numerical counts for each style and each background) could be kept hidden and, through a simple formula, "normalized" (to keep the numbers from getting out of hand) while maintaining a relative ranking to each other. By simply "voting" one way or another again and again as they appear over the course of days/weeks, the more desirable/appealing displays would end up "winning" and get displayed more often as desired, while those that someone is tired of seeing could easily be suppressed by multiple SHIFT+DOWN presses (for a style, or SHIFT+LEFT for a background image).