Although I have some reservations about the D, and even though we lost Quinn, Collins, Heath and Jones, I still believe we are better on defense than last season. The scheme is going to help a ton, plus there is no doubt we're stronger and deeper in the middle at DT. Those two things alone should help this team a ton. Games are won in the trenches you know. And as long as teams can't just pound us up the gut all game we should be ok with our corners and S's.
Our 2 stud LB's should be put in much better positions to succeed than previously. McCoy and Poe are big additions, literally. They will really solidify the middle freeing up the LB's to attack the ball freely. They shouldn't have to deal with free running OG's filling the lanes all game anymore. Gallimore, Woods (once re-signed) and Hill should all learn from them and take big steps forward quickly.
Those things should have a very positive effect on our sack total from last season too. Even with our current crop of DE's, which I think is decent as is, the O-line will have to help the interior guys block the DT's so our DE's should have more success. A rotation with DLaw and Crawford at LDE with Armstrong and Anae at RDE should be better than ok. Adding Smith and Gregory may make it even better, but I wouldn't count to much on that, at least not early on.
I'd still want to bring Griffen in, he could really help IMHO. But even if they don't they should be much better than a year ago.