Buffalo Bills and Miami Dolphins
Buffalo has road games in Denver and New England, and some difficult home games against Green Bay and Kansas City. The Bills will probably need to pull off a big upset or two to get to 10 wins.
Miami has similar problems, possibly even more acute. They travel to Denver, New England and Detroit. They have tough home games against San Diego and Baltimore. The Week 11 home game against the Bills is nearly a must win for the Dolphins because of tiebreakers. (Buffalo already beat Miami in Week 2.) We still don't expect a wild card team to come out of the AFC East.
The entire NFC West
St. Louis is out of the playoff mix, so they don't really count for the purposes of this post. (But their schedule is brutal, too.) Arizona, San Francisco and Seattle all face difficult roads to the playoffs in part because they have to play each other.
The Seahawks still have to go to Arizona and San Francisco, in addition to road dates in Kansas City and Philadelphia. Those will all be difficult games.
Late in the season, playoff contenders want a few games where they are heavy favorites. Those are hard to find in the NFC West, where the three contenders could all inflict damage on each other.
Kansas City Chiefs and San Diego Chargers
You'll notice a theme in this list. Division teams have very similar schedules, so the difficult paths are grouped together. San Diego might have the toughest closing schedule on this list: at Baltimore, vs. New England, vs. Denver, at San Francisco, and at Kansas City. The Chargers' game in Miami this week could quietly have huge playoff implications.