Dallas could be a SB contender in 2-3 years, just in time to give Romo and Ware a small window of contention, IF the Cowboys make moves that Jerry is unlikely to make.
1: Hire a GM with full control over players and a hefty scouting department
2: Hire Ryan Dennison from the Texans - the Kubiak/Shanahan offense is literally the perfect offense for Romo (athletic mobile QB that has tremendous deep accuracy - basically the stuff that RGIII does now is what Romo should have been doing his entire career), and Murray is a perfect ZBS back. Maybe you can bring over one of their defensive assistants as well.
3: Get a RT, Smith will be fine in a ZBS blocking scheme, and you can probably get away with your interior with a OL friendly blocking scheme.
4: Invest in the lines, though you can get away with lower-grade linemen running ZBS, but your interior DL is aging
5: Have Jerry stay out of the way.
Alternatively, you can replace Step 2 with hiring Sean Payton, but there's no way Payton doesn't go back to New Orleans imo; there's probably not an offer that he can't refuse.
Dallas still has a lot of talent - a LOT of talent. With the right coaching, they can retool into a SB contender. Problem is, the right coach isn't gonna come to Dallas with Jerry's management style.