The NFL is declining, not only in LA but places like Jacksonville. Time to get rid of some teams. If they move to London, you will see this same effect. In fact, the Raiders are about to be in for wake up call when they move to Las Vegas and the crowds aren't there.
An 8 game schedule in London would be interesting. I believe that in 2018 the NFL is contractually obliged to play 5 games here..... 2 at Wembley, 2 at the new Tottenham stadium and 1 at Twickenham.
The move to Tottenham is interesting because it is 60,000 capacity unlike Wembley and Twickers which are 80,000 plus. I don't think the NFL could sell Wembley 8 times a year.... Tottenham? I absolutely believe they could based on the continued strong sales for 4 games 10 years plus into the experiement and with novelty value worn off.
The issue in London will less be about selling the games and more I think about building a partisan fan base. I know a lot of folks who go to the games.... I only know 2 Jags fans and one of those long pre-dates the London games. People go to see live NFL football but they still support the Patriots, the 49ers, the Giants, the Dolphins etc...