Cowboys' offseason grade: B+

Scouts Inc.'s Matt Williamson is playing the professor role, grading each NFL team's offseason roster renovations.

Williamson gave the Cowboys a B-plus in the ESPN Insider piece. A sample of his analysis:

The Cowboys' cornerbacks look to be incredibly improved with the addition of Brandon Carr in free agency followed by an aggressive draft day trade up to secure Morris Claiborne, a potential shutdown corner, at No. 6. Teaming those two with Mike Jenkins and Orlando Scandrick should allow Rob Ryan to finally trust his cover men, resulting in much more aggressive defensive play calling from a pressure and blitz standpoint. There is a chance Jenkins will be traded before the season, but the Cowboys still could use a lot of nickel personnel (even on early downs) considering the wealth they now have at corner.

Staying on the defensive side of the ball, Dallas also looks stacked at inside linebacker. Sean Lee is already a great player, and Bruce Carter, a great talent, could be due for a breakout season. Plus, the Cowboys signed Lee's college teammate Dan Connor as insurance. Connor is a very solid two-down player who excels versus the run.

The Cowboys' defense clearly has improved, and the offense remains explosive and has plenty of high-end talent. Don't overlook the addition of Kyle Orton as Tony Romo's backup, giving the Cowboys one of the best backup quarterbacks in the league. But there are two considerable holes on this side of the ball. With Laurent Robinson leaving for Jacksonville and Coale's injury in minicamp, Dallas has very little at wide receiver behind Miles Austin and Dez Bryant. That limits the personnel packages the Cowboys can feature. Also, although the Cowboys brought in interior offensive linemen in free agency, I don't think any of those guys is an upgrade or the answer -- and Mackenzy Bernadeau recently had hip surgery. However, new offensive coordinator Bill Callahan is one of the top offensive line minds in the NFL.