This is more for once you're level 50 and above, but I personally liked to do the roulettes with the quicker DPS queues - trial, alliance, normal raid, MSQ. Then I'd mix in beast tribes, Potd/HoH, daily hunt marks, and FATES. Frontlines is also a really good XP chunk, but the queues can be a bit iffy at times. I lived on a diet of boiled eggs since they are insanely cheap from an NPC, and all food gives the same XP buff.