I practice all kinds of positions.Try standing on 1 foot at 30 yards and you will see how important a secure and solid,balanced base is.
I like to sit on my but facing the target at 30 yards.I also like turning my body so that I am shooting almost completely backwards.I feel confident that I could take a deer with these shots out to 30 yards.
Sitting is actually my favorite position to shoot deer because there is a whole lot less movement required and I can shoot as well sitting as standing.