I saw some dufus on YouTube today explaining how much money the NFL could save if they just went to a geographic realignment. In addition to saving the league money (who knew in 2016, that would be a concern) it would help save the planet by reducing transportation costs and carbon emissions. Here was the guys 4-team divisions (no conferences)

Northeast: NE, BUF, NYJ, NYG
Atlantic: BAL PHI, WSH, PIT
Southeast: CAR, JAX, MIA, TAM
Southwest: ATL, NO, HOU, TEN
Midwest: CLE, CIN, DET, IND
North: CHI, GB, MIN, KC
Rocky: DEN, DAL, ARZ, SD
West: LA (Rams), OAK, SF SEA

I looked a the map and decided how easy it would be to tweak this into something better. For one thing, the NFL is never going to want the two NY or LA teams in the me division for marketing reasons. Secondly, we now have some teams moving so here's a better update:

Northeast: BUF,BAL, NE, NYJ
Atlantic: CAR, NYG, PHI,WSH
Southeast: ATL, JAX, MIA, TAM
Southwest: DAL, HOU, NO, TEN
Midwest: CLE, CIN, IND, PIT
North: CHI, DET, GB, MIN
Rocky: LA (Chargers), ARZ, DEN, KC
West: LA (Rams), LV (Raiders), SF, SEA

Yea, some of these divisions change little, but they make both geographic and rivalry sense.