On top of the MMR issues, one of the most frustrating things about PvP is the movement lag. It's impossible to kite a warrior in the charge radius, and you get hit by AoE effects that were clearly out of range on occasion. If an enemy player isn't afflicted by a slowing effect, I cannot hit them unless I run in front of them (I have 120-150ms which isn't high enough for this to be a normal issue). Sometimes, I will shadowstep to a mounted target and appear 15 yards behind them, out of range to even reach them with a sap. I've had my arena partner get hit by spells while he was behind LoS, because it seems as if the server isn't accurately displaying the location of every player, meaning that while he was likely behind LoS on his screen, he probably wasn't on the other person's. On top of this, there are many things they could port over from the AT core, such as spell delay, that would allow for actual blizzlike gameplay.