1. The ability to use our spells on siege vehicles. Cutting out all my curses, drain life and siphon life makes aff locks in particular near useless in LWG and SotA. Stop trying to apply real life BS to the game like "you can't drain from machines". Guess what, in real life there isn't magic to begin with.
2. Some armor. Level 80 cloth armor is actually LOWER than the level 70 cloth. Worse yet, 10 levels makes the mitigation % much lower. I went from 23% melee mitigation to 11%. A very undue nerf to clothies. I realize melee aren't getting armor pen on their pvp gear but at least their damage goes up from 70 to 80. Our mitigation actually goes down.
Do something like make demon armor increase the armor from our cloth to that of mail quality according to each piece's item level. Stripping the heal bonus from fel armor wasn't a good change for pvp considering demon armor's armor bonus doesn't matter if it makes a difference of having 0 armor vs. having 0 armor after armor pen.
3. A use for our new spells, demonic portal and shadowflame.
Demonic portal was a very narrow sighted design on Blizzard's part to begin with. It looks to me like it was considered for arenas and no other aspect of the game. Even in arenas pvp is too spontaneous and too mobile for warlock's to be expected to have time to put down a portal ahead of time, and make sure they move away from it but not over 40 yards just so they can use a watered down blink. Allow warlocks to use an AoE cursor to select where they put the portal and take the cast time off.
I love Ghostcrawler's explanation as to why shadowflame was given to locks. "It does shadow and fire!" Great, something half baked for both affliction and destro. Put simply its an inferior AoE and does too little damage to be worthwhile on a single target. Hey, it's a watered down cone of cold! I get it, warlocks aren't allowed to have anything mages don't already have but better or else they'll whine about warlocks. Make shadowflame a single target spell and give it some actual damage. A moderate cooldown damage on demand spell would actually be useful.