If you think about it the biggest problem facing this game is that toons become replaceable and irrelevant. What not remove the level caps and reward long service to this game ?
If a player can keep leveling a toon over time it would open the gates to a much more diverse roster. Obviously the gear and requirements would scale with toon level but it would reward strategic grinding and saving of resources.
The rings idea is good in theory but once players have maxed toons out we are back to square one and in need of another reboot.