Pokemon Buddy System Exp Rewards
If you've played pokemon at all (especially X and Y), you are already aware of this type of system.
If not, wouldn't it be nice to be able to pick a "Favorite" class in your list of available Desciples (L/H/M/W) and gain a small amount of experience towards that class every time you gain experience on any (edit)level 50 job?
Nothing too crazy, but just a little extra here and there so you can continue to level up that level 31 MNK, while doing your high level roulette as DRG or SCH?
Maybe you REALLY HATE playing a Gladiator/Paladin, but you NEED to get provoke as your Warrior. Set Gladiator as your current "Favorite" and (edit) do your Warrior dailies, then get Gladiator to level 22 for provoke after a while without playing it at all!
This will work especially well when new classes/jobs are released and you have like 40 classes to level if you ever hope to get ALL of the cross abilities, even if you don't want to get them all to max.
(edit: I like the idea of it only being available to get bonus experience as a level 50 job so experience isn't wasted, especially for people who don't enjoy leveling more than one job.)