We are definitely getting younger and more athletic. But almost all the defensive replacements will be downgrades, at least in the short term. It is hard to assume rookies are going to step in a play lights out.
Prepare for the worst, hope for the best. If some of these kids pan out we can be right back in the thick of things in a couple of years.
I think that is the faulty assumption. I think you will have a step down for some of the starters, but the others will be almost automatic improvement because of how bad their predecessors were. Whoever replaces Pace, Scott, Thomas, Greene will most likely be an improvement by default.