Bad idea:
1. There is far more to managing than being able to "light up a clubhouse". Baseball being an everyday sport, that will wear thin very quickly.
2. We have no idea if he can manage. He's never done it before. How does he handle a pitching staff, starters and pen?
3. As a recent retiree, he is waaaay too close to the current team. If he were going to or coming from another team, it MIGHT work. When 80% of your roster was his teammate 9 months ago, they aren't going to see him as a manager, they are going to see him as a teammate.
4. Why in the world would he WANT to manage? It is a thankless task where everything you do is criticized, and in Boston, that includes how you have a bowel movement (okay, I'm exaggerating a little bit here). He has a young son, doesn't he? I'm sure he wants to be around to see him play youth ball, etc. And at some point, he would have to be fired; almost all are.
I'll say the same thing I said when Varitek was the popular ex-Sox that people wanted to see as manager. Maybe someday, but not this soon.