Well since it only comes out in a month from now, it's not a huge wait. You could always level crafters and gatherers in the meantime, as well as most of the beast tribe stuff. Leveling DoW/DoM classes and the MSQ are a pretty small section of the game.

Only you can decide, but there's plenty of things for you to do in the meantime if you choose to wait. You wouldn't be wasting your sub or anything.