well i main a druid on wow and for pvp im usually around 2k (for rbgs atleast) so i wouldn't say im high. i play horde and alliance, i have friends on horde with whom i raid and do pvp with, and then on alliance i only pvp. most of the players i know and play with on alliance are sticking alliance, and a couple horde friends are switching. because for horde currently you have the blood elf racial yes, but if you want to seriously pvp at the moment, you mostly run a undead for the racials. now in legion the human racial only will negate stuns, but in my eyes that is still more effective than fears and the like, because if you are running with good people fears don't mean anything. and the silence for blood elves is 2 seconds, with a 1.5 minut cd, which in a 10 minute arena can get a couple uses, but seeing as you have to run next to them to use it, many ranged classes are put at a disadvantage if they have to get near the enemy melee, and the healers can see it coming(because a ranged person only charges the healer to cc in most cases). so all in all, im going to be sticking alliance for pvp and horde for pve, and i am sorry for the wall of text, but those are some reasons and examples to why i think pvp is still going to be tipped towards the alliance.

en.wikipedia.org/wiki/Undine