Agreed, its always tougher for a QB when you don't HAVE to blitz. That leaves 7 in coverage and that is something I believe kaep may struggle with. Only rushing 4 also allows you to have a spy (like you said) without forfeiting much (if any) in coverage. And yes, a major key is fresh lineman......and no fua.
I have a feeling we will see a lot of the defensive ends also dropping off into zones. The thing is, we have got to stop the run so we don't fall into the lull of bringing 8 in the back. As soon as we do that the option opens up as well as the stretch runs to the right side.