Morris, Kirksey and especially Hitchens have just stepped up their game this November. They will be huge losses but there are capable, physical, not completely green players waiting for their turn.
To me the bigger question is, when the backers struggle in pass coverage next year, how will Phil P compensate. That guy has shown the ability to adapt his defense from abused to abusers and even found a way to mask the glaring weakness at safety by not give the other team enough time to attack them. Unique to this staff, Phil P decided that he could either sit in base and get beat or take the risk of attacking and give his team a fighting chance. I think the D will be ok.