Even without clinching a bye, there's a good chance the Saints could have the #3 seed wrapped up before week 17. If that happens and there is no shot at the #1 or 2 seeds by then, I would expect most of the key starters to sit that final game against the Panthers. So basically that week would be treated as a bye and/or preseason game.
As for the playoffs... if the Saints do not finish with a bye, I'm pulling for a rematch with the Bears. I think they're the best matchup for the Saints. They pose absolutely no threat in the passing game to take advantage of Shanle, Dunbar, or Harper. And their propensity to run 7 step drops plays right into Gregg Williams's hands.
Their defense is also straight forward and doesn't blitz much. Great QBs take advantage of that.