Bulaga and Shields will be fine. They played an entire season with the team, and they played at a high level. I agree big time with your comments on Lang, Neal, and Burnett, though. And Wilson could certainly use some practice time.
I think the free agents will be hurt the most. We don't know which ones (if any) will end up staying with the Packers, but those who do will be coming off a period of being in limbo, so the season may get off to a weird start for them. I'm thinking of Jones, Colledge, Bigby, Barnett, etc.