I'd like to see them get back to a 3-4 base.I know they run a lot of different fronts but I think the personnel they have is better suited in a 3-4. Left to right Long, Brown, Flowers with Nink, Hightower, Mingo, Sheard at LB. It gets Sheard, Flowers, Nink and Long all on the field at the same time. I would like to think that would generate some pass rush.
I think a 3-4 makes sense. One of the sacks Sunday was on a play where the blocking scheme matched Ninkovich on a RB - they need more stuff like that, because Flowers is the only one who can beat an OL one-on-one. I'm not crazy about the group you laid out, either in coverage or in run defense. I could see something like:
3-man DL: Flowers - Brown - Branch with Long rotating in for Flowers and Valentine / Hamilton for Brown and Branch
4-man LB group: Sheard / McClellin - Roberts - Hightower - Ninkovich
In regular nickel situations, one of the big guys comes off and Sheard / Ninkovich play on the ends, but they still have some disguise possibility with Hightower's ability to rush
In passing situations, get Mingo or Van Noy on for Roberts to give even more pass rush / blitzing / disguise dimension. Hopefully one of those guys can cover, too.
I don't think the secondary is as bad as it looked last Sunday. Butler and Ryan are a good tandem. Ryan has been a roller coaster ride his entire career but overall he's not an awful corner. Coleman may not be the answer at nickel. What happened to Jonathan Jones anyway? Is he hurt? Cyrus Jones sucks. I called it when they picked him but I was hoping I was wrong. He's not even a consistent KR... DMC is still great. Chung is lost in coverage but that's nothing new. He can't defend deep. He's the one they should have spying the RB.
I think it's time to pull the plug on Cyrus Jones' returning - I just don't see any way he gets to trustworthiness this season. He's flashed enough talent that I'd like him to get another shot next offseason, but I'd hate a playoff game to come down to him fielding a punt cleanly. Focus on his development as a defensive back. He's better in press than off, which also describes Rowe and Ryan, so run a press-heavy scheme and live with the fact that teams will hit you with man-beaters (as the Seahawks did).
Not sure why Collins was let go now. Even if he wasn't having a great year or not following orders he was a presence that opposing offenses needed to account for. I hope Sunday wasn't a sign of things to come, more just Seattles offense outplaying our scheme.
The depressing part to me is how bleak the future looks. There was a hiccup from 2009-2012 or so where the old guard of defenders like Seymour, Rodney, Vrabel, Samuel, Bruschi, etc. all got old and got cut or retired, and the team needed to transition to a new defensive core. It looked like they had pieces in Hightower, Jones, Collins, McCourty, etc. But now we're back to rebuilding the D again. Jones, Collins, and Easley are gone. Hightower, Sheard, Ryan, Butler, Harmon, Long, Mingo, Branch aren't under contract next year. Ninkovich is old, and McCourty and Chung are getting there. Are they going to built a great defense for 2017-2018 around Malcom Brown and Elandon Roberts? How does this unit get better?