Perhaps a color-code? Similar to the way the #-of-views text color changes (subtly) under questions listed herehere.
So the most-viewed (or most-voted) Related questions float to the top, in a color-coded fashion. Color code could even be based on a combination of views, votes, answer status, etc. This might be more subtle than a number, but I think that's the beauty of it. It's an easier way to view the information.