We have 3-4 major holes on defense with nobody on the current roster to fill it.
1-tech: Was a weakness last year. Collins didn't fit well there. We either move Collins back to his natural position and have him backup Irving or we play him out of position again. Worst case scenario: Someone steals Irving from us and then both DT spots become a need. Best case: Collins gets it together and becomes a solid 1-tech next to Irving. Likely case: Collins backs up Irving at 3-tech and we need to find a starting 1-tech.
MLB: We lost Hitchens and rumor is Smith is moving to SLB. Even if we moved Lee back to MLB, we'd still have a need at MLB or WLB. Worst case scenario: Lee goes down, Smith continues to struggle, and we don't have any reliable LBers. Best case: Lee stays healthy, Smith plays how he was expected to out of the draft, and they become a solid duo and make the 3rd LBer less of a priority. Likely case: We have WLB and SLB covered with Lee and Smith, and a major hole to fill at MLB.
Both safety spots: With Jones moving back to CB, we just lost our starting FS. And I don't know how confident they are in Heath at SS. Best case scenario: Woods becomes to FS we always wanted Jones to be and Heath looks like a true SS. Worst case: Nobody steps up and we have no reliable safety. Likely case: Someone steps up, likely winning the SS job, but we need another starter.