Incentivise tanks and healers to actually play the game please.

[Naberrie]

I be interested to hear your thoughts for a solution that meets that requirement.

How about this: if you run a leveling roulette on a capped job, instead of receiving tomes or clusters you get a consumable that grants 50% percent of the exp required for next level that can be used on any job. So you could run the roulette on a tank for the quick queue, but then use the consumable on your DPS. You get a fast queue, plus exp on your DPS.