I completely disagree with your tasks that the players we let go were very good to great. Long has been way overpaid, often injured, and his play went from bad to average. Laurinitis was slow and was a drag from behind tackler. Jenkins played very well but got a ridiculous contract that of course we wouldn't dream of matching. And McCleod became a better than average safety but also is being paid like a 10-time Pro Bowler, which he is not. Thinking that Quinn, who was one of the top defensive ends in the NFL coming back healthy would be an upgrade over C Long is a 100% guess.
Predicting Ogletree will be a better player than Laurinitus is a no brainer in that Tree already was. Thinking Gaines could replace Jenkins makes sense as he beat our Tru as a rookie and was our #1 CB. And do you really think that Fisher and Williams don't have a replacement for McCkeod? Fisher's one of the top defense-minded coaches ever. He played in the secondary. He developed McCleod from an unseated player to a guy who just got paid millions. I trust Fish here. When the bullets start to fly and Quinn joins AD, Brock and Hayes with blitzing from Tree, Barron and Ayers opposing QBs will be running for their lives and throwing the ball anywhere to avoid sacks. I think we'll have it covered. I really expect our D to be much better with more sacks and turnovers. Not worried even a little.