Pro for keeping him/staff: with lead, they can be as aggressive as any D in NFL. With creative blitz packages and personnel that can defeat anyone one on one, the front seven is respected around the league for the difficulty they represent.
Con against keeping him/staff: without lead, they are on field way too long, the "bend, don't break" philosophy can be exploited be ball control offenses to tire out the D and this makes closing out close games extraordinarily difficult for a D that has likely played 35 mins or more.
It's why teams all played us the same way. Take every point early, don't be proud. Slug out an early lead and ball control. Win the game in the second half.
If we have a new HC that puts a premium on scoring and the team improves significantly, including improving ToP, the only question that matters is this:
Do you believe that GW's D would be successful with better support from the offense (more points, playing with the lead, better Time of Possession, etc) or do you think that the defense's issues would still ultimately manifest regardless of the success of the offense (can be up by 24, but a ten yard cushion is s ten yard cushion and quick completions are how teams come back...)
I dunno. I see both sides, but I haven't put GW through my Pattern-o-meter. Can't really since I don't know who the HC of the OC is and without that... Too many variables. I'll maybe try for that overdue dead horse post...