I'm going to make my case for Jim Caldwell.
He was the QB coach for Tony Dungy and won a Super Bowl with the Colts in that role. Stayed with Dungy until he retired and replaced him, went 14-2 in his rookie season as HC and made it to the Super Bowl. He was 14-0 until they rested the starters after locking up home field for the playoffs. As a rookie, had he not rested his starters, he may have gone undefeated! I understand he had a very talented team with prime Peyton Manning, but he did nothing to get in the way of that teams success (like our coach routinely does) and was there the whole time they were building it under Dungy. He had a good year after that at 10-6 and a playoff appearance and then was coach for the Manning injury season when they Lost for Luck and then he was (in my opinion unjustly) fired.
He followed that up with becoming the QB coach and OC (mid season promotion) in Baltimore a year later and helped them win the Super Bowl, somehow getting Joe Flacco to look like an MVP in the playoffs.
He turned that into a job as Head Coach of the Detroit Lions where he spent 4 years going 11-5, 7-9, 9-7, and 9-7 with a franchise almost as hapless as the Browns. He was the winningest coach for the Lions since the 1950s, which would also probably be the case if he put those same win totals in 4 seasons with us. I have not fact checked this, but anecdotally it seems true because we've sucked for a very long time, just like the Lions.
I have no idea if he's interested as he took a year off, then got hired by the Dolphins this year but left due to family issues. If he is interested though, this is the guy we need to look at. Strong history as a QB coach, OC, and Head Coach. Got Joe Flacco to look elite and win a Super Bowl. Been on the biggest stage multiple times for multiple teams so he knows how to win. Had winning records 3 of 4 years in freaking Detroit of all places who had way less talent than we do.
He's an ideal candidate for us.
Think he's interested?