Personally, I liked it when the Dolphins used the 4-5 defense against Buffalo in 1992, which is what we used when I was in high school.
Five defensive backs and only two linebackers. Even though I was listed as an outside linebacker, I was a roving linebacker who would shadow the running back. I could line up in several different spots depending on the type of play that was called. The other linebacker pretty much blitzed on every play.
Reminds me of what my HS football team ran. They did the 4-4 , 3-5-3, 4-6 bear set which was confusing but effective.