I would switch to the 46 playbook, it still has 4-3 plays, but it is a better overall playbook.
Here is my setup:
Ends: Harvey, Groves
Dt: Henderson, B. Smith, Knighton
Linebackers: Ingram, Durant, D. Smith
Corners: Cox, Starks, Witherspoon
Free safety: Mathis
Strong Safety: Nelson
I play a lot of cover 2, so I switch mathis back to safety and get more speed on the field.