NFCE
NJG (Clinched Division and Homefield throughout playoffs)
Washington
Dallas
Philadelphia (Wild Card)
NFCW
Arizona (Clinched Division)
Seattle
San Francisco
Seattle
NFCS
Atlanta (Wild Card)
Carolina (Clinched Division)
New Orleans
Tampa Bay
NFCN
Chicago
Green Bay
Detroit
Minnesota (Clinched Division)
AFCE
Buffalo
NJJ
Miami (Clinched Division)
New England*
AFCW
Denver
Kansas City
Oakland
San Diego (Clinched Division)
AFCS
Houston
Indianapolis (Wild Card)
Jacksonville
Tennessee (Clinched Division and Homefield through playoffs)
AFCN
Baltimore (Wild Card)
Pittsburgh (Clinched Division)
Cincinnati
Cleveland
The toughest division is, IMO, the AFCE. Probably being a homer but it's close. The other candidate for toughest division, IMO, is the NFCS. Teams are pretty stacked up in those divisions and there are some good teams that will miss the playoffs because they play in those conferences. The AFCN has Baltimore and Pittsburgh but the two other teams suck. JMO
The weakest is much easier. Hands down I think it's the NFCW.
With more FA signings and draft yet to come it's hard right now but it's fun to talk about.