I think we can all agree that this game has a lot of content which most people barely ever even touch.
Not necessarily because they don't like those quests, but because the amount of EXP that they get from the quest just cant compare with the top farming spots.
Now we could just increase the amount of EXP they give, (or decrease the EXP of their competitors) and that would solve the problem.
But unless you got the balance juuust right, then all you would end up doing is changing what quests are the go-to quests for their level while possibly introducing some new problems.
So here is my idea, it would be a new system called Maverick EXP.
Maverick EXP would be a global bonus of up to +100% EXP on a quest, which decays by 0.1% (0.05% for raids) every time that quest is completed by anyone on that same server.
And the bonus would be increased by 0.05% every time any other quest within the same level range is completed.
Multiple runs, and additional players (but not hirelings) within the same instance would count towards this.
So a team of 5 people with 1 hireling, running a quest twice would count as 10 completions.
Epic variants would be calculated differently then their heroic counterparts.