I'd love to see that too, but it ain't gonna happen.
I doubt they could pay Brady enough to do it as a regular gig, where he has to "report" to the studio and "rehearse" and take "suggestions" from suits who have no idea what they're talking about. I could see him in the booth or studio before the Super Bowl, though.
I don't think we fully understand (at least I don't) that Brady is in another stratosphere of global celebrity than a Dungy or Harrison or Bruschi or, when he's done, even a Peyton. Put it this way, several of those guys are in New York every day pretty much during the season to do their shows and they're never in the tabloids here. All Brady has to do is attend a benefit or opening and the papers are full of pictures of him and Gisele.
My guess would be that Tony Dungy is probably the highest paid former NFL'er in the studios now and I'd be surprised if he earns a lot more than $1MM, maybe $1.5MM, for four pre-season weeks, 17 regular season weeks, four Playoff weeks and various "Promotions" and "Specials," plus all of the film work and rehearsals he has to do; in other words, it's pretty much a full time job from August to February. I doubt that would be attractive to Brady who no doubt already earns a multiple of that on his Investments alone by just waking up in the morning, let alone on his endorsements and ownership interests in Under Armour and other companies he shills for (not to mention his salary).