The Carolina Panthers made their offensive line much better with the acquisition of Travelle Wharton. The 10-year veteran might only have a little tread left on the tires, but he is a flexible player who can (conceivably) play four offensive line positions in a pinch. Out of the gate the Panthers will ease him in at left guard, but the best spot for him in 2013 will be to supplant Byron Bell at right tackle.
Cam Newton is an anomaly. Most quarterbacks struggle with blindside pressure, but he handles elite pass rushers well. Where Newton fails is front side pressure from a blitzer in his face. Call it confidence or hubris, but Newton tends to try to dance away from rushers he can see, often being forced into an ill advised throw, or taking the sack. Conversely, his favorite move to avoid blindside rushers is to react to pressure by spinning away from the would-be tackler, and turn up field.
There's something to be said for making a strength stronger, and putting the two best pass blockers on the left side -- but it would be far more beneficial to keep Amini Silatolu at left guard when he returns from injury, and play Wharton as the team's right tackle.
The best line the Panthers could play this season would be Gross/Silatolu/Kalil/Williams/Wharton. It allows Silatolu to continue to develop while being sandwiched (read: mitigated) by the team's two best linemen, while improving the pass blocking on the right side of the line.
Wharton is unquestionably the best left guard on the roster, but there are diminishing returns at work if you swap out Silatolu for him. Going back to 2009 and 2011 you'll see that Wharton is an somewhat-accomplished offensive tackle. These are his position grades from Pro Football Focus when playing tackle:
-0.4 overall (-0.9 pass, +0.5 run)
A negative grade isn't good, but Wharton is a godsend compared to Byron Bell over the last two seasons (-25.7 overall). The veteran excels where Bell struggles, and when paired with Cam's weaknesses it's a natural progression.
Deciding on the correct offensive line makeup prior to Silatolu's return is a moot point. What the Panthers are doing right now is correct, but shifting Amini to the right side is a poor decision for a player still trying to adjust to the NFL. Put your best players at your most important positions, and mitigate the guards -- this means Gross, Kalil and Wharton need to be the keystones of the line.