As the topic title implies:

Give a baseline bonus of gil for the adventurer in need, but increase that amount based on how many of the other roles are currently waiting in the queue.

I just queued into a Mentor Roulette as a DPS and the average wait time is 13 minutes.

There are so many DPS in the queue right now that a roulette that covers all content but savage/ultimate, still has to wait 10+ minutes. Could you imagine if you were trying to solo queue into an optional dungeon like say... Amdapor Keep (Hard)? You'd be waiting for hours.