A note on leveling at 90 - you could stay in Pandaria, but the XP difference in Draenor is worth it. I am almost 95 and have only just unlocked my first two followers in the garrison. Long way to go and I'll be in Legion before any of it is done.
We're levelling through Draenor by treasure hunting with the Handynotes addon. Haven't done any quests after unlocking the Garrison Hearthstone, and we got to 98 after about three hours of flying around. Not sure it's much faster than questing, but it's a nice change of pace!
