There absolutely are common 'styles/shapes' of racks. Around here I don't know of any real theme, I've seen a lot of different shapes.

There was about a 4 year run a short while back, where I, guys in my group, and some neighbors that I'd talk to in maybe a 3-4 sq. mile area, were killing a lot of bucks with kickers on the G2's. I killed several with kickers on both G2's as well.