My suggestion is to have an option to change the color of the background, font, header title, or even put an image as a background.
This will make the leaderboard of each games unique and will fit the art style of the games. This will attract more developers to use leaderboard, be more creative, and to be consistent in terms of the style of the game.
Hope this feature will be up soon! I’m one of the developers that will definitely use this!
