I think you miss the mark here. Peck's eastern character seems to have more class than the wester ones, but down deep, when it come time for the nut cutting, James McKay proves just as hard as the Major, Rufus or Steve Leach.
I would call it a comparison of manners between the Old East and the Old West...
BTW in real time in the film now on TCM, the Hannasseys have Julie Maragon hostage and Jim has just found out. The shinola is headed for the fan!
Nah, I find the Peck character an annoying do-gooder.
BTW, a much better Western role for Heston was "Will Penny."