There isn't a linear list of HCs from top to bottom. Each job in the league is different, and each comes with a completely different set of challenges. Some organizations are setup so that it's virtually impossible for *anybody* to win in those cities. I'm looking at you CLE. Some combinations of coaches and front office are combustible, but effective. See, Harbaugh in SF. But those have a short shelf life. Some organizations have HoF coaches or a system that they leverage over long periods of time. PIT, NE and probably GB at this point are the most obvious examples here. SEA, if they can demonstrate the staying power, might eventually enter this group.
Beneath that, you have perhaps a handful of teams that have good enough combinations of players and coaches that they can jump up and be competitive or even win it all under the right circumstances. The Saints. The Giants. The Ravens. Zimmer and the Vikes might be entering this territory, too. I had thought the Cowboys were entering this territory going into the season. That's still where I'd probably put them, but this season was a giant curveball.
Below that, you have the teams that are just in disarray or in the very early stages of sorting out a new plan. There are a ton of teams in this category, obviously.
For my money, Belichick, Arians, and Harbaugh (if he were in the NFL) are the cream of the crop of NFL coaches right now. With a caveat for Harbaugh because he's so prickly he's unlikely to stay anywhere all that long. Of the guys who might work well in Dallas, given the ownership and the media attention of the Cowboy job, Payton is about the only guy I think represents a clear upgrade to Garrett (and even he has the substance abuse issues that are a question mark). There are guys working their way up the ranks right now or in college who I think are intriguing, but they're also unknowns.
But to at leas try to answer the question--or what I think you're really getting at, anyway--I think we've probably got a better situation in terms of how our staff fits with our organization/situation than probably 75-80% of the teams in the league.