Hate for this to be my first post on the forum, but I have to agree with a lot of what is being said here.
I was one-shotted the other night in Voidstar at level 44 with lfull vl40 pvp gear, and that same person managed to kill four of us before we could take him/her down (44/43/43/39).
Fighting players with full expertise is akin to banging your head against a wall, it really takes the fun out of pvping.
I'm happy that they are pulling level 50's out of pvp soon, but since I am only two and a half levels away from 50 I'll soon be back in the same boat...
One thing they could do to fix this imbalance is possibility nullify expertise against fresh 50's for a certain amount of time/warzones so that they have a chance to catch up.
I don't base my pvp experience on winning and losing, I actually prefer close matches regardless of the outcome, but getting rolled because the other team is running full gear is lame.