They should just remove it for battlegrounds and in Arenas and rated bgs they should just make everyone wear the same (pvp) gear. That would Allow everyone to enter normal Battlegrounds and have some fun without farming 2 weeks while beeing raped by everyone And make the Rated PvP Balanced.
Obviously it's too hard to manage a correct balance when pve gear has three offensive stats (primary + two ratings) and pvp only two. PvP geared people must be able to kill, which means PvE geared people will be able to burst in a CC time frame at the end of each expansion with WotLK/Cata model.
My opinion :
PvE gear lacks defensive stats for DPSers and healers. Blizzard should introduce a "pve-resilience" which would be necessary in pve to avoid one-shots / avoid oom healers. Make sure the stat is present on every pve piece (with same exception as pvp pieces). pvp resilience is 60% effective in pve, pve resilience is 60% effective in pvp.