No need for a downgrade in the CB department. Have we even seen what Ogbonna is capable of? People are so quick to write him off, forgetting that Bonucci was an absolute disaster, a calamity of cataclysmic proportions his first 12-18 months here.
As for the AM/TQ (not the guy who sings I wanna fuck your sister, no) position, we need someone with pace, vision, good passing range, high footballing IQ, and stamina (as The Cusp rightfully stated earlier).