Ideally in my opinion it should be moderately time-consuming to level up (1-50 should take 2-3 weeks). They should change the class quests around a bit to be like a limit break system, perhaps as tutorials on how to play that class. As they are now with guild points abolished, they only serve to give free exp. SE did a great job implementing and making the job quests meaningful but they need to do something with the class quests now.