There is a way to display the current stats in the Game window, and it's via the <stats> layout token. I think that token was added in version 3.2. It's not terribly flexible, as it displays the columns and values as they are currently displayed on the Stats tab of the Settings window. But it's better than just showing the Settings window to your players.
However, since the built-in screens don't currently allow for token substitution, you can't display this on the Player Rankings screen, only on a screen of your making.