Our defense will absolutely improve. 3 reasons why....
(1) We have a loaded/experienced backfield. Even though Cooper played CB/NB last year, he has experience at Safety and knows the defense. Even though Jackson didn't start at Safety, he has experience there and knows the defense. Combine that with Gerry & Martinez. We have a lot of athleticism there. As for NB/CB's.... we're loaded with experience.
(2) We have double the depth at LB with way more speed and athleticism. Santos is back, Anderson is back, throw in some of those touted RSFR and FR and we'll be great there.
(3) We have a lot more depth at DL with more athleticism. At end we've got Ankrah, Moss (if he is still on the team), McMullen, Gregory, Mixon, Suttles, Natter, etc. At tackle we've got Randle, Guy, Williams, Curry, Valentine, Maurice, Collins, etc.