From HFP, go to zangarmarsh then to Nagrand. if you're not 68 by the end of nagrand, either go to shadowmoon valley or netherstorm. do not go to blades edge. it has a terrible terrain. also avoid terokkar forest, especially those quests to kill arakkoas and find some eye/gem or something. annoying if you box it. but do quests from the stranded caravan and the base southwest bonewastes if you do decide to go to terokkar.

in zangar, not only do you have your own faction's quests, you also have the cenarion expedition's quests to do.
in nagrand, there's nessingwary and then your own faction's quests. plus some rock elemental's quests.

in netherstorm you can quest out of area 52 or out of the stormspire.
in smv, you can quest out of your faction's city there or from the aldor/scryer town.