Also minus 3 for missed P.A.T. or field goal less than 39 yards. If the software will support it you can give points for forced fumbles. You can allow a defense to play to its personnel by allowing variations on defensive schemes. I also like the idea of using a coach. I give 6 points for a win.
Many people are opposed to using coaches till they try it.
For example if you have Cowher you will become a Steelers fan instantly. It put something back into football that had been gone for me since I started fantasy football. Another very interesting idea for those who seek realism is to subtract your defensive score from your opponent's offensive score. So if my D scores 25 and my opponents O scores 50 then his score is 25. It is serious bragging rights if you shut someone out.