I think Ted's major problem was that he didn't immediately replace all the players that left.
Thompson failed to replace Corey Williams adequately, and he failed to have a contingency plan when KGB never recovered from his surgery.
That's my biggest issue with him at this point, can he have players ready to replace Driver, Woodson and Harris, Taush, Cliffy when they retire, not a couple of years later.
Thompson has proven he can fix weak areas on this team (RB last year, DB couple of years before), so I don't think it's something to really worry about. Regardless, Ted has got to start getting players that will be ready to go exactly as some of the important vets on this team can't maintain a high level of play.
This off-season though, Ted's priorities have to be the lines. O and D lines need some boost.
The NFL: Where Greg Jennings Happens.