Las Vegas would be a fantastic place IMO to have a team, LA aswell.
I'd love to see the league add 8 more teams, 4 more in the U.S 4 outside of it. 1 more team per division, this would make the spread of talent alot wider, and would give alot more people high paying jobs, helps the economy. People will get money to build 8 new stadiums, people will work in them, people will work scouting, management, coaching, players, waterboysetc; economically it would be fantastic for the U.S, and earth.
Toronto, Mexico City, London & 1 more city get a team, this would be highly controversial, but I would love to see the disparity it would create, I don't like that one year a team is a SuperBowl contender and the next they are one of the worst in the league, or one year a team is the worst in the league and the next year their in the playoffs. I would prefer it a process, 3-4 years for a downfall, 3-4 years to buildup, im not sure many people would agree on that, but having 40 teams economically would be a huge boost to the local markets economies, plus would bring money from other countries into ours in the form of high paid athletes, who are historically lose with their money.