I think they have great potential, starting with the defensive front/pass rush. If you can rush the passer well, good things happen. Turner, Verse, Fiske, and Young are a great nucleus. And I don't think any of the 4 has peaked. Add in Ford as a run-stopping presence and, if they can get Stewart or Jackson to adequately fill Hoecht's role (an understated hole to fill), then they'd really have something. I think Tyler Davis will take a step forward as a depth piece on the DL.
I also think the combination of Landman and Speights at ILB will be better than what they had early last season with Reeder and Rozeboom.
Their biggest question mark defensively is CB. Witherspoon, Williams, Durant and Forbes should all be ok. But are any of them more than ok? But again, if you can pass rush and defend the run well, that can mask shortcomings at corner.
Then, with young guys like Hamilton, Paul, Dolac, etc. maybe one of them becomes a contributor/rotational guy as the season wears on.