On absolutely every BG there is some AFKer, who only take place on BGs. Also on Alliance where you wait much more for que, it will be a little bit better if the AFKer gets kick for 30 mins or 1 hour ? On most of the BGs players dont report the afkers, that is good for the AFKers, but sometime there are some players who know how to make 2 clicks and report.
So my suggestion is, IF it si possible to make the deserter time for kicked AFK players to be more than the normal deserter time.