Raiders probably have the worst HC/OC/DC combo - friends of mine that are fans are wanting Del Rio fired, and have preached it for months. I was thinking the difference between him in winning in Oakland and bottoming out in Jacksonville was the presence of a franchise QB, but Carr just looks like one of the most overpaid players in the league right now. They let a successful Bill Musgrave go because they thought our ol' QB coach Todd Downing was a rising OC candidate, so they promoted him and it looks like a total failure. As for defense, it's inexplicably sucked for the past several years even though Ken Norton was a very good on-paper hire from Seattle years ago.
It's been a weird tenure for Reggie McKenzie - he's definitely hit on several draft picks, but Dennis Allen and Del Rio were both very bad hires. Yet another high draft pick to go with the QB, pro-bowl filled OL, passing weapons, and a defense that can be righted by proper coaching should keep them in good shape though.