So I've always been about integrating narrative elements into my mechanics. What if we took the archetypal behavior of our character classes and made them into OOG rewards?
The idea would be that players fight over a set amount of bonus EXP per session. At the start of each session everyone has an equal share of 100% bonus exp. (4 players = 25% bonus exp per person) At the end of the session, the GM could award an amount of extra exp to the party. (Or designate a set percent of exp he would have given as bonus exp)
-Playing a Rogue means you are allowed to cheat. Go ahead! Lie about your dice roll! If anyone calls you out on your cheating- your dice roll automatically fails! The GM must ALWAYS strive to catch the rogue cheating! For other players... it's just a suggestion. (And your out of game bribe of chips and mutual aid could help them...)
-Paladins have to watch the other players. If any players they attempts to cheat at all or use a rule incorrectly to their advantage and the paladin's player calls them out on it, they get 50% of their remaining bonus exp. (At the GMs discretion) They do not have to CORRECT the rule, just call them out on the fact that they are in error.
-Wizards need to be Rule Nazis. If they correctly correct another player on a rule works (using a book as a reference) they get 50% of their remaining bonus exp. (At the GMs discretion)
-Rangers are guides. If the table descends into OOG chatter for more than 5 minutes and the ranger alerts the GM, the Ranger gets 25% of ALL players remaining bonus EXP.
Just an idea.