I think the whole direction needs to change.
Unfortunately, the whole organization is grasping at straws from year to year. Obviously, it starts with the owner. I am not confident he can fix this thing that has been broken for so many years. Teams like New England, Pittsburg, Green Bay, New Orleans, Baltimore, San Fran, NY Giants seem to get it right most of the time. What separates them from the rest? A quality President, GM, and coach. We are missing all three. It's not that Mayhew has done a crap job. It's more like he is just not on the same level. Lewand has very little power for a President and has never been held accountable. Ford Jr. is hog tied by Daddy.
The Lions will probably can the coaching staff and hire another marginal coaching staff.
The John Gruden's of the world will find the Lions tempting because of their talent but get scared off by the GM on up. It just is not a winning organization and any Gruden type's will find that out in short order during his interview.
I hate to be negative but this is the reality in my mind.
Good GM replacements? Omar Khan, Eric DeCosta, and Brian Gutekunst come to mind. Khan would probably be able to get Cowher to come with him. Now is the time for the Ford's to seize the day and restore the roar in Motown. Heck, they may even make some money doing it.