The ability to lean your boat and maintain upright posture is an essential skill for running whitewater.  We use the J Lean for ferries, peel outs, and hole surfing.  I find this skill easier on boats with edges than rounded boats.  You should be able to angle your boat 30° and paddle in a straight line for a distance - a drill I personally enjoy doing.  Here is a short video describing the J Lean and head placement: J Lean.