I see that Battlemaster gear is beign discontinued, something that I feared will eventually happen after they discontinued Centurion and Champion, and now a new PVP set is beign introduced, this is what people call vertical progression, the idea that once you get to the endgame you progress throgh the game by adquiring gear that is numerically more powerful.
I think this is a bad direction for SWTOR to take with regards to PVP for several reason. First, It's grindy at it turns people away, designers might think that a bigger carrot on a stick it's gonna keep people playing but that's not actually the case, almost every PVPer I knew moved on to another game, mostly because they are done chasing carrots, people should PVP in your game because it's fun, because they want to earn prestige among other players and for their skills and achievements to be recognized, not to chase carrots, that is antiquated design if you ask me.
Also, Vertical Progression completely devaluates all your former achievements. Hey remember how hard you worked to get your Champion or Battlemaster set? What an achievement! well guess what? those sets are now obsolete so all that work you put into the game is now pointless, this turns people off instead of keeping them hooked.
Many new games have been moving to Horizontal Progression, which means that as you progress in the endgame instead of getting more upgrades to your gear, you get sidegrades, you get different options. I've been playing Planetside 2, they do this pretty well, Guild Wars 2 does this to an extent and also League of Legends, for anyone that has played LoL, Riotgames doesn't keep their players hooked by introducing more powerful runes, they do it by introducing a variety of different champions, and while the game is not perfectly balance, no game is, but if they decided to start selling Tier 4 or runes or Tier 5 of runes intead of new champions the game would die almost immediately.
In my opinion all PVP sets should be equally powerful and the differences should be only cosmetic, maybe you would want to add different set bonuses when you get all 5 pieces, but stat wise they should be relatively equal, I think that simply recoloring an old set and slapping a bigger stat number to it it's pretty cheap and lazy from Bioware, and probably that's why they do, it because it's cheaper and easier, but if they keep going that route they will end up turning everyone off.
Here are a couple of videos on the matter that I find really interesting:
"Power Creep" from Extra Credtis
"Why Games Should Scale Horizontally Instead of Vertically" by Taugrim