I dunno if I'd put Mike Shannahan in that category as (quite frankly) he's was less than spectacular as GM in Denver and his record in DC was worse than Jim Zorn's. If RG3 works out though, he'll look much better.
I'll say this for Billicheck, while his drafts in recent years have been less than spectacular he has adapted well to the changing times. This is how I would rank coaches with a little reasoning.
1.Bill Billicheck- Yeah he got lucky with Brady, but he has adapted to the changing times.
2.Jim Harbaugh-Gets the most out of his players, no better gameplanners in the NFL.
3.Tom Coughlin-Built an expansion team into a very good team rather quickly. Also built a good Giants team that has won 2 Super Bowls that can pretty much plug bench players into the starting lineup.
4.Sean Payton-Team is lost without him
5.Mike Tomlin- Struggling with aging players now, but he's able to get the most out of lesser players.
6.Mike McCarthy- Took over a depleted Green Bay team and took them back to the top. Good guy to be face of a franchise
7.John Harbaugh- Never been eliminated in the first round of playoffs. Quietly morphing the Ravens into a good offensive team while restocking on defense.
8.Mike Smith-Matty Ice aside, has morphed a directionless franchise into a well respected and well coached one. Could move up if/when wins a playoff game.
9.Andy Reid- Constantly finding talent out of nowhere. Lack of a Super Bowl win hurts him. Looks like his Philly career is close to an end.
10. Lovie Smith- Took a directionless Bears team and morphed them into a Super Bowl team. Constantly getting good defenses and potentially has another Super Bowl run in them
11.John Fox- Wore out his welcome in Carolina but does have a track record of building tough teams
12.Mike Shannahan- it is hard to ignore his 2 Super Bowl rings but that was a long time ago. Been a bust so far in DC, but with RG3 looking solid and the emergence of Alfred Morris, he might start to rise again.
13.Gary Kubiak- For years was Mike Shannahan's right hand man in Denver. Built a great offense in Houston. Will move WAY up if they win Super Bowl but still has to win more consistently.
14.Jeff Fisher- Calm down Fisher bashers, a lot of unproven coaches is a huge reason why Fisher is higher on list. Also does a good job rebuilding fallen franchises. Needs to get more consistent results (ie wins)
15.Marvin Lewis- Longevity. Good job changing the culture in Cincy. Needs to win consistently.
16.Ken Wisenhunt- Got Cardinals to Super Bowl. Hall of Fame accomplishment on its own. Struggled to find QB since Warner retired, tends to throw players under the bus quickly.
17.Jim Schwartz- Helping to make the Lions respectable. Needs to win consistently and get more discipline on his team
18.Leslie Frazier- After a horrible first full season, he's got his team playing very good football. Long overdue for shot at being head coach.
19.Pete Carroll- Took over a Seattle team in need of rebuilding and brought in a lot of talent making the defense dominant. Needs to win consistently.
20.Joe Philbin- Could go hire. First time coach, looks good so far. Has time to move up.
21.Rex Ryan- Once a great HC prospect but his style has a shelf life. Team's rapid decline this year main reason I have him so far down list.
22.Chuck Pagano- Like the changes he decided to make to the Colts in their rebuilding. Hopefully he recovers from Leukemia.
23.Mike Munchek-Winning season his first year, team looks lost this year. Reason for his position.
24.Jason Garrett- Once seen as a rising prospect in the coaching ranks, is a little over his head in Dallas. Too much too soon.
25.Norv Turner- Decent OC, mediocre HC. Wasted the prime years of a very talented San Diego team. May have one or 2 more shots at playoffs with current team
26.Dennis Allen- Young coach that raised quickly for the ranks. Like what he's trying to do, but has a long road ahead of him.
27.Mike Mularkey- Failed as Bills HC, tough job to make the Jags competitive. In his defense though, there have been glimpses of why to be optimistic. Needs to deal with being part of a poorly run franchise
28.Greg Schiano- Interesting hire, but is trying to change a culture. Poor offense, but has team playing tougher.
29.Ron Rivera- Got his long overdue shot at being a HC. Team looks to have regressed this year but they do have a lot of young players. Time to move up list depending on how rest of season goes.
30.Romeo Crennell- Had the team finish nicely at the end of the year, but he's not really the right coach for Chiefs.
31.Chan Gailey- Team was a bit overrated coming into the year. Goes through spurts where team looks good. Too inconsistent to be higher and no winning record.
Pat Shurmer-Poor guy is crippled by a horribly run franchise. Actually has a nice system on offense and defense, but he's with the Browns.