I'm not sure I can deride Jerry Jones as a GM quite so readily. He put together a team that won 3 superbowls. If that was done by listening to other people and getting lucky, he still gets credit for listening to the right people and for having enough luck to choke an elephant. The Cowboys aren't thought of as a team with no talent; they're thought of as the team with plenty of talent who manages to squander it annually.
But as others have suggested, minimizing Jimmy Johnson's role in things to the point Johnson left, and the ego that suggests, that seems to be a legit criticism, and may well turn out to be the fatal flaw when all is said and done because underneath every decision about who will coach the team is the desire to prove that mainly Jerry Jones is the reason for success. That sort of mixed motivation seems likely to continue to lead to mixed results.
With that, have to agree with the rest around here that the best coach for the Cowboys is a splashy one, a Gruden type.
Bevell can perform when he's on a team loaded to the gills with talent, he's done so in Minnesota and here, so he probably wouldn't hurt your offense, but the offense isn't the problem in Dallas is it? Who knows if Bevell as a head coach could sniff out and reel in (with Jerry's permission) an excellent DC?
Quinn has done a really fine job here. I applaud how he has been willing to use the team's (nearly infinite) strengths on defense. Think he's still a bit young, and not sure if his performance in Seattle translates into him being a guy who can transform a really poorly performing defense. It's just really difficult to form a complete opinion of a coach who took an elite defense and turned it into an elite-elite defense (and who also has the benefit of 2 or 3 excellent new pass rushers that last year's D did not have).
Norton Jr., I dunno, LBer coach is even less cachet. I feel like Jerry would eat him up, even he did possess some transformative qualities as a head coach.