It looks like our defense might be pretty good this year. We have the best secondary in the NFL. We signed two veteran 3-4 players, taking one of Baltimore's starting DEs. The secondary will give our pass rushers longer to get to the QB and collapse the pocket. Not to mention that if Kyle Williams and Troup keep playing up to their training camp levels, combined with Stroud and Edwards being stout against the run (Carrington also performing well in practice), our rush defense looks to be much better.
The quality and depth of the players in our secondary will also give George Edwards the ability to blitz more often, and that should help with pressuring the QB. Maybin seems like he can be at least be an effective 3rd down rusher.
Also, teams historically do better against the run in their first year of the transition to the 3-4 defense. It doesn't seem, barring injury, that our run defense won't be much better against the run. This does translate into a nasty defense. If our run defense was top 10 we would be elite.