Figures... I was reading through this thread and the last post is the one that came up with the same idea I did.
Though I was thinking about a small percentage chance of token in end chest, with it guaranteed at 20th turn-in. Trade in token plus 2 ToD rings for ToD ring of choice. The only problem I see with this is people keeping a ring they don't need but someone else does, simply to turn it in for the one they want.
I also like the idea of a ring for each class. How about a placeholder for the ring of each class, with the +6 based on class, and the +1 exceptional of your choice when you turn in placeholder. This way a tank could even choose +1 Exceptional Charisma if they wanted for that extra point of Intim.
The downside to any changes to the system is that people who previously killed themselves to get their ring could be quite upset. Of course, it could also be a distinguishing mark, that you got your ring BEFORE they made it easier.