Its about time to let Pathfinder go for old content as new Players or Players who came back ,need a lot of time to get there whilst missing out the progress on the new expansion.
OH, and let me buy BFA flying too when SL is released...I worked for the other 2.
I feel like 5-6 vanilla zones probably take as long as an expansion to play through, and many races have obvious places to start (as in just start them where they would have started before all of this), then you take allied races, etc and just start them at the most obvious zone (allied races with no obvious start you give them the human or orc treatment after they join the alliance/horde).I imagine it'll be something like this: Play through the most obvious 4-5 zone progression path (such as Elwynn> (player picks between Westfall or Redridge)> Duskwood> Stranglethorn> (player picks between Blasted Lands, Swamp of Sorrows or Burning Steppes) and then maybe end off by picking a cata zone (as in player gets access to the portal in their capital and just port them there so they can pick anyone, cause why not).
There really should be an option to access the world without the whole cataclysm mess...
I can't imagine that the Cataclysm zone levels is intended. It's supposed to be paced so that leveling through vanilla or any of the expansions will take you to 50. If you had to run through all of vanilla AND Cataclysm to get to 50, nobody would choose that path. I'm not saying a ton of people will, but it wouldn't make sense.