While I agree that it's very unlikely Tom would ever coach. (too much time, in fact MORE time than when he was a player and too many other opportunities ) BUT he's be a great coach simply because he WASN'T a naturally gifted athlete. He MADE himself into the all world QB be became. He BECAME a 'strong armed' QB because of all the work he put in to improve his arm strength. Brady won games with his mind as much as his body. His greatest natural gift was his ability to process what he saw after the snap of the ball better than anyone. To get the ball to the right place, to the right guy and do it quickly
Brady has SO much info to pass on. He'd be the ideal QB/passing game coordinator coach. He's an 6th degree black belt in footwork in the pocket, and a Nobel prize winner in reading the defense before the snap and what to look for after it. He could coach a guy on just what to do in order to strengthen their arm. And now that I think about, he'd be a great play caller as well. Finally, Brady, over the years, was taught by great TEACHERS who knew how to communicate what he needed to do to become great. From BB to Tom House, Brady surrounded himself with great teachers. So I believe he would know how to pass it forward.
So I believe Tom WOULD be a great coach, but is it likely he will be? No.