After more than a week of free-agency action, it's time to take stock of what teams have accomplished thus far. We'll assign highly scientific and inarguable grades for each NFL team's free-agent haul thus far, noting their additions and subtractions. The NFC North is below. **
Credit general manager Ryan Pace for overhauling Chicago's long-time 4-3 defense to suit Vic Fangio's 3-4 scheme. After hitting a home run with outside linebacker Pernell McPhee last offseason, Pace upgraded at inside linebacker this time around, adding the dynamic duo of Danny Trevathan and Jerrell Freeman. The Bears also signed Akiem Hicks away from the Patriots to bolster the defensive line. This is a defense on the rise.
On the other side of the ball, Pace finally found a taker for disgruntled tight end Martellus Bennett, picking up a fourth-round pick from New England. Re-signing Zach Miller on the heels of a breakout season made that deal easier for Bears fans to swallow. Grade: A-
Calvin Johnson's retirement left the Lions reeling. New general manager Bob Quinn did well to come away with the pick of a weak wide-receiver litter, but Marvin Jones will deal with a lot more defensive attention in Detroit after feasting on single coverage opposite A.J. Green in Cincinnati. Although Quinn re-signed a few key defensive players in Haloti Ngata, Tyrunn Walker and Tahir Whitehead, he failed to add impact talent on that side of the ball. Grade: C+
Death, taxes and Ted Thompson watching from the sidelines in free agency. Thompson is a tried-and-true roster builder -- drafting, developing and extending homegrown talent. Mike Daniels is a perfect example of Thompson's approach to free agency. While the Giants threw $50 million guaranteed at Olivier Vernon, Thompson locked up a better player with a $12 million signing bonus in mid-December. The loss of B.J. Raji to hiatus was mitigated by Thompson's foresight to extend Letroy Guion's contract in February. Grade: B
The Vikings' plan is easy to ascertain: Upgrade the offensive line after NFL rushing leader Adrian Peterson was held under 100 yards in five of the final six games of the 2015 season. To that end, general manager Rick Spielman added mauling guard Alex Boone and mammoth right tackle Andre Smith. Wide receiver remains a question mark after disappointing speedster Mike Wallacesigned with Baltimore. Although Stefon Diggs exceeded expectations as a rookie, he's more of a second fiddle as opposed to a legitimate No. 1 receiver.
On defense, it will be interesting to see how much longtime Titans safety Michael Griffin has left in the tank after Tennessee released him in February. Grade: B-
