After watching Seattle, it's pretty evident the Packers are quite a ways off in terms of overall talent level. I think the offense is fine. The defense needs an impact player at safety and holy hell do they need pass rushers. Look at the safeties playing in the NFCC game. Packers have nothing close to any of those players. They also need to view Matthews as a luxury and not a player to build the defense around. He's just not able to answer the bell enough. Misses way too many snaps and games. I'd actually consider trading him as he's really the only valuable player outside of Rodgers that the Packers could trade. I know this won't happen but the point is they need at least 2 more guys in the front seven that can bring heat.
This. I've been hard on Capers the past few years but I don't think it really matters who their defensive coach is with the talent level they have on defense.
The year of the Superbowl, the defense was considered one of the best in the game. They collapsed the following year, and it goes far beyond the fact that they lost Collins. Yes, it contributes to the problem, but the reasons Capers is a major part of it...
Strategic level: Drafted defensive players stop developing almost entirely after their first year. There are many examples of this and it's the single greatest reason why Green Bay has been spinning its wheels since 2010. This is a coaching issue. With the right guidance, players are expected to take natural steps each year. This doesn't happen very often under the current defensive administration.
Tactical level: Complete inability (or unwillingness) for the defensive gameplan to adjust to what the opponent's offense is running. This is why Green Bay is notorious for allowing the same guy to burn them time and time again during a game. This is almost entirely a defensive coordination issue. Example: When Kapernick is nearing 300 yards rushing on your team, at what point do you hold 8 in the box until they find another way to consistently beat you?