So the NFL top brass (and the Baltimore Ravens ownership) have not had the best few weeks because of their negligence in regards to domestic abuse. The NFL TV ratings, however, still are doing quite fine.
The NFL is still growing (unless Goodell wants to kamikaze the league) and gaining new fans domestically and overseas; so much that they may expand in the next 5-10 years. How many teams? I wouldn't be sure, but I can't see it being more than four teams max to bring the team total in the league to 36. The division would need to be realigned too.
It wouldn't be the smartest idea parity-wise because teams still consistently struggle to find a quarterback to lead their offense and some teams struggle to sell-out games, but monetarily it would be in the NFL's interest and the NFL loves'em some money. More viewership will lead to more ad revenue, and then MAYBE it could lead to overall lower ticket prices but that may just be a pipe dream.
These are the ten potential cities that the NFL could open up expansion teams in the near future; these are in no particular order and will only be continental US cities (sorry London). I could see a team being in Toronto, Canada some day, though. I'll add a few choices for nicknames/mascots but that's not completely important here.