With the NFL draft and the better portion of free agency behind us, most teams have made their biggest moves to improve their rosters for the 2012 season. Looking at the additions so far, I see several units that have been improved this offseason. On Thursday, I examined those units in the NFC. Today, let's take a look at the AFC, focusing on the upgrades by the Pittsburgh Steelers, Buffalo Bills and Indianapolis Colts.
Unit: Offensive line