Outside of shoring up the defense.. the Pats offense is in pretty good shape, other than getting that game changing WR if it can get one. With Gronk and Herny locked up for at least 3 years, a developing, and young, RB corps, if Welker can be around for a couple more years as he has not slowed down, Brady has some weapons at his disposal which will still give teams nightmares for a while to defend. So, it is entirely plausible, if health and if his play continues at an elite level, Brady can get to, if not close to, playing until he is 40 and with the Pats. If anything moves Brady, it would be if he feels he needs a team to give him more support and no longer feels the need to be the only playmaker on offense. He now has a few more weapons with the Pats in place to extend his career here.