I personally would be pretty nervous if Marinelli was let go.
Our D has its flaws but they are sound enough to hold the fort if our offense can improve by even 50%. Those defensive players and especially the DL would run in front of a bus for Marinelli and I really worry how much the D might regress next year if we brought in a new DC and had to manage a whole scheme change on that side of the ball at the same time as installing a whole new offense.
On top of which, I would really like to see Marinelli get a chance to stretch his wings and use some of our promising younger players (Shea, Wootton, Melton, Conte, Hardin) to freshen up concepts that have gone stale. As Rivera could tell you, Lovie, kept a tight grip on how "his" D was run and there may be new wrinkles Marinelli has been itching to try and finally would be at liberty to do.
Any or all of the offensive staff can be out the door yesterday as far as I'm concerned... but I think keeping some continuity on our D will be critical so I'd say hands-off as far as that unit goes.