Free agency is one piece of the NFL roster-building puzzle, best analyzed in a broader context. Bill Polian, Louis Riddick, Matt Williamson, Field Yates and I accounted for that when putting together team-by-team report cards for the signing period that opened two weeks ago.

September is a long way off, of course, and even the best-laid plans are sometimes no match for what awaits in the regular season. But in applying some time-tested principles -- rating teams on their abilities to address needs before the draft while keeping their own best players from departing -- a consensus formed around some of the teams (Green Bay unanimously earned an "A" grade, for instance).

Other teams sparked debate and questions. Do the Bills deserve credit for aggressively pushing to close the gap with New England in the AFC East? Perhaps they do, but their approach stands in stark contrast to the one that earned the Packers our highest grade to this point in free agency. The Saints, Eagles and Jets also were major movers in the market. There was much to consider when analyzing their approaches, and those for all teams as the 2015 draft approaches.

In order of their letter grade, here are our evaluations of how every NFL team has done thus far in player acquisitions this offseason:

'A' Grades

Green Bay Packers

Grade: A

Key re-signings/additions: WR Randall Cobb, RT Bryan Bulaga, OT Don Barclay, S Sean Richardson, QB Scott Tolzien

Key subtractions: ILB A.J. Hawk, DE B.J. Raji, ILB Brad Jones, TE Brandon Bostick, CB Davon House, ILB Jamari Lattimore, WR Jarrett Boykin, CB Jarrett Bush, FB John Kuhn, WR Kevin Dorsey, QB Matt Flynn, CB Tramon Williams, DT Letroy Guion, RB DuJuan Harris

The Packers have taken homegrown roster-building to the extreme, rarely bringing in players from other organizations. Whether or not you think the Packers should be a little more proactive on occasion, there can be no questioning the general soundness of their approach. Finding a way to keep both Cobb and Bulaga made this free-agency period a smashing success.

"They did a great job keeping their own and that is really all there is to say about it," Polian said.

Yates called this a "classic Ted Thompson offseason" while Williamson emphasized the flexibility Green Bay now enjoys while heading into the draft.

"They would get my best grade," Williamson said. "You could make an argument that they were the best team in the league last year even though they lost a crazy game in the playoffs. They have a great offensive playmaker in Cobb and a very good right tackle in Bulaga. That offense is loaded. Now they have the whole draft to do whatever they want."