um...wat? I went from 1-50 entirely off quests, I ended up about a bar and a half from level 50 when I finished the last quest chain in Stillmoor. They planned out the leveling process incredibly well, actually.
Beyond that, after running tier one dungeons and getting in full epics, then running tier two dungeons and getting in a new set of full epics, there just...wasn't anything to do.