I found that my biggest jump in river reading ability came when I backed off of the paddler in front of me. I stopped trying to follow his line and started to look ahead and pick my own.
Always look ahead. If you are only running one move rapids "tunnel vision" won't hurt you but anything else and you need to see the whole rapid... And see all possibilities in it. Clean lines, bad lines, places to recover, ect... And don't forget the run out either.
"We should restore the practice of dueling. It might improve manners around here" -Edward Abbey