I like the way it is right now. If you want to start PvE you can use your PvP set and if you want to start PvP the leveling gear will do alright as long as its augmented. If you want to do PvP in your high end PvE gear, you will get crushed, if you want to do high end raiding, your PvP gear wont be enough. The lowest rated PvP gear will lend you better stats, than any PvE gear just as it should be (now that they worked on the bolster system for about a year ). The gear difference between the 2 PvP sets is small enough, that you can win against players, if you are slightly better than them.
Expertise will give you better results in PvP than any other stat. I guess thats the idea behind a "PvP stat"