I think Jaylon Smith gives us a good shot in the arm next year, if healthy, which all signs point to him being 100%. Pair him with Sean Lee and we have one of the top LB groups in the league on paper. I like Hitchens, not the best but if Hitchens is your third best linebacker I think you are doing OK.
We got next to nothing out of Cedric Thornton this season, a real disappointment, but I think he returns for at least one more season. Tapper never saw the field, Collins was OK, and David Irving showed he can be dominant. Demarcus Lawrence hasn't lived up to his draft status, he needs to be an 8-10 sack a year guy, injuries held him back this year, but even when he was on the field it was less than impressive. We need to add a PLAYER along the defensive line. I think that one addition is the key for this defense.
The secondary is going to cause problems, to many free agents at the same time. Carr will probably be gone. I would like to keep Mo, but it would have to be a decent price, he is hurt to much too pay big money. So that leaves us with Scandrick, Brown, Jones, Wilcox, Heath. You almost have to resign Church, but again, he's not a player I want to throw big money at. The key here, to me is, as long as we don't regress and we add the player on the D-line we should be fine. I would prefer to not have to settle for "fine" and go out and get a top end player to help steer the secondary in the right direction.
I think you can create enough cap space to get two playmakers on the defense. If we do that I think we go from fine to pretty damn good.