There's slightly more work to it than I originally expected, must admit.
But you CAN just add different icons. You can have a group and rank image. We make multiple groups, 1 medal, 2 medal, 3 medal, and apply a member to the group which they fit. So they can be a rank, ie, Sacred, and be in the group "2 medals". etc. You can edit the user's permissions by group.
I've actually started work on this, but with this forum skin the medals don't lay out nicely, this could be fixed either by editing the CSS, or by changing theme - that's one of the main reasons I've been looking at new themes
"I searched through the alterable values of flug gb.mfa but couldn't find Eric, Hoj, Alex or the Spaghetti Monster. Therefore Eric must exist, but Hoj, Alex and the Spaghetti Monster must not exist."