Like almost no other sports league in the world, the NFL is excellent at perpetually creating uncertainty. Even on the most dominant teams, uncertainty and upheaval regrows as surely as Kurt Warner's facial hair.
And every offseason, teams are forced to make critical decisions. It's the nature of the game — and before the lockout when the NFL wasn't crazy, there was a salary cap that further equalized things.
There isn't a single team in the league that doesn't have some lingering issue for either the remainder of the offseason or into the regular season itself.
Understand that almost every team has more than one lingering question, so I'll just highlight each team's biggest issue.