MoP which needs more players ? a or h

i dont like to be in a faction with more players cuz it outbalance bgs,etc.. so i prefer goin to lower populated faction..

You can check the information page, its quite equal

https://www.warmane.com/information

Depending on the time you play you should choose alliance (evening hours, after 1pm server time) or horde (morning hours, till 1pm) and you will pretty much have an insta que for BGs.