The reason why Huttball is picked most of the time is probably due to the fact it has a higher % to be picked. Let's start with a 33.3% chance to get in all 3 war zones, but then factor in the possibility that you can que up Huttball against your own faction, and if you are on the overpopulated side of factions, your going to be playing 50% of your warzones in Huttball whether you like it or not.