Good question and one that I haven't asked anyone just yet. But it would be hard to play Knighton a lot because they'd likely be in a lot of nickel situations against teams such as Philadelphia and New England. However, my guess is he'll still play. Denver played a 4-3, so it's not a direct comparison, but against the Eagles in 2013, Knighton played 40 snaps and vs. New England last season he played 41 (he played 30 against the Colts). Certainly, Denver would have been in nickel looks much of the time, and the Redskins' nickel is more of a 4-3 look. So you can play him in those games and still be OK.
With Max Unger anchoring an improved line, the Saints' offense will revolve around Brees, wide receivers Marques Colston and Brandin Cooks and, more important, the one-two punch of running backs Mark Ingram and C.J. Spiller, who spent the previous five seasons in Buffalo. Ingram had a breakout year in 2014, notching career highs in rushing yards (964) and attempts (226) and inked a four-year extension in March. Spiller, meantime, is the type of dual-threat back (a la Reggie Bush, Darren Sproles and Pierre Thomas) that Payton has in the past used to exploit mismatches.
The starting left tackle is projected to be Michael Oher, who will be trusted to protect Newton's blindside after struggling mightily the past two seasons in Baltimore and Tennessee—as a right tackle. Mike Remmers is currently penciled in at the other tackle spot. The 26-year-old was pressed into starting duty late last season when Nate Chandler got hurt and did okay. But there's a reason a reason he's been in six organizations since 2013, right? There are other options, such as Jonathan Martin, rookie Daryl Williams and Chandler, but they'll need to leapfrog Oher and Remmers.