After a year in which a team went undefeated in their division yet missed the playoffs and another division was barely won by a team with seven wins (yes, seven wins), I would much rather seen an expansion of the postseason, rather than 18 games for every team.
Instead, the NFL should add another Wild Card week in order to adapt to the increasing amount of parity in the NFL.
I would even suggest that the additional wild card teams could be voted in by coaches, media and fans.
It might be too late to stop an 18 game schedule in the NFL, but to me, it makes far more sense to simply add an additional week of the playoffs, with two extra wild card teams.
This year, two teams with ten wins missed the playoffs, the New York Giants and Tampa Bay Buccaneers, while another team, the San Diego Chargers, finished with nine wins; the Raiders went undefeated in the AFC West and missed the playoffs, which seems like a BCS-type of argument.
Obviously, that kind of thing won't happen every year, but considering the fact that the NFL wants to expand the schedule to 18 games, it seems only reasonable that the postseason should also expand.