The best short odd picks to win the AFC are the Colts and Titans. At 6-1, the Colts have a better shot to win than the Chargers at 5-1 and as good as the Steelers at the same. The Titans, the best team in the NFL last year are currently getting 9-1 odds. You will not find better odds than this.
In the middle range, I like the Texans at 18-1. When it comes down to it, there are six teams with a chance to win the AFC and the Texans are one of them. Considering the Dolphins are 20-1, the Texans are being underrated.
If you like long shots, the Raiders provide the best money, at 50-1, you get a team that is as likely to win the AFC as the Bills are.
Forced to make a pick, the Colts are the most likely AFC Champion.
There are three teams with a real chance to win the NFC, Philly, Chicago and New Orleans. My pick to win would be the Saints. At 9-1, the Saints somehow have worse odd than the no-chance Panthers. The Eagles at 6-1 aren't terrible.
The longshot pick would the Niners at 25-1. Now I don't give them much chance, but giving them the same odds as the Bucs is strange.