The personnel would agree.
Leslie Frazier and Joe Cullen were both brought in from the Tampa Bay Buccaneers to coach the secondary and the defensive line respectively. Frazier's addition has been talked about. He was the coordinator in Tampa Bay and in Minnesota in both instances ran a 4-3 base front.
Joe Cullen is the addition that really makes one think. Coming over from a team who ran gap shooting principles leads me to thing it is likely the Ravens will employ some, if not most of their concepts.
The Ravens have the personnel to run a 4-3, though a few tweaks would be needed in certain positions.