While most peg the defense or special teams as a cause for concern I dont. Let me explain.
The special teams unit has been infused with hungry young rookies and they have added Joe DeCamilis who will not allow for the same mistakes that consistently happened last year. If the Dallas special teams is only average it is a HUGE improvement from the previous years. In addition McBriar returns from injury and we now have a kick off specialist.
The defense was an enigma last year. They were absolutely dominant at times and then absolutely atrocious sometimes in the same game. In my mind the two weakest links on the defensive side of the ball were Zach Thomas and Roy Williams/Pat Watkins/Keith Davis at SS. Adding Gerald Sensabaugh and the rookies will upgrade the SS position to where its at least respectable and no longer an obvious weakness. At the same time replacing Zach Thomas with Keith Brooking is an upgrade. Let me clarify this, obviously Zach is a better LB then Brooking but not in Wades 3-4 scheme. Zach Thomas said on numerous occasions he was not comfortable playing ILB here. Keith Brooking flourished and had his best year in the Wade Phillips 3-4 he will be comfortable. He will be able to plug the hole on 1st and 2nd downs and then either Bobby Carp, Jason Williams will come in on 3rd downs.
Which brings us to the offense. My biggest concerns are Jason Garrett's playcalling tendencies and the health of the WR's. Last year everyone who watched at least one Cowboys game knew that on 1st down it was a pass, 2nd down a run, and on 3rd down a pass. Garrett suffered when Sparano left for Miami and he gave up on the run to quickly in games. Garrett is a smart guy (Ivy League graduate) so if anyone can turn it around it would be him. In addition to losing Sparano I believe that Garrett suffered because D-Coords like Jim Johnson were able to study his tendencies during the offseason and recognized patterns and formations and thus the offense became predictable. He is every bit as important as Romo in regards to the success of this team IMO.
The WR position at first glance has alot of depth and talent. Roy Williams, Miles Austin, and Patrick Crayton are a fine 1-3 WR. Add in Sam Hurd and Stanback and you have potential. But here is the problem Roy W, Austin, Hurd, and Stanback are all injury prone. They have a history of injuries which is troubling because if 1or 2 WRs get hurt suddenly your looking for a FA from the street. I gaurantee you that I will holding breath everytime a WR gets tackled because I realize how serious an injury to that position could be.