Last season the Packers were 5th in total defense, 5th in yards/play given up, 13th in passing yards given up, 9th in QB rating given up. They did this with JA playing only 1/3rd of the defensive snaps. They bring back Nixon (94% of defensive snaps), Bullard (nickel, 72% of snaps), and Valentine (50%), while adding Hobbs. Hobbs replaces Stokes, Robinson will likely replace Rochell/Ballentine, and they bring back two guys who were late round picks last year in Hadden and King.
I said before the draft that one of the big factors in the draft was how the Packers felt about the development of Hadden and King, and given that the Packers didn't draft a CB until the 7th round and given that they released JA, the tea leaves suggest that the Packers feel good about Hadden and King as backups.