Manning should retire and coach Denver. His past injuries are showing, but he has a great instinct and knowledge of the game.
We watched him here in Indy for many years. We love the guy and we can tell he is not on top his game physically anymore.
Great players rarely make good coaches. Good coaches need to motivate players, and teach those that lack the physical gifts to maximize their talent. Great players are self motivated and have the gifts. Good coaches come from the ranks of players that had short tough careers that involved a lot of washing out.