Look, obviously we need a QB. But it's otherwise not as bad as you imply.
On the OL, we return 5 guys who have been starters at various times. Yes, we lose Thor, but Levy was in and out of the starting line up and never impressed anyone. I would have expected better OL play this year even without a coaching change.
On specials, a punter is a punter and the one we lost was fine but not an All American. And at kicker, while Puyol developed well we know Tarbutt basically kicked him equally in the lead up to the 16 season because he started the year as the long kicker. We may have a step back at both positions, but it shouldn't be a panic.
The DB situation is certainly iffy, but if we want we can start two Corners who have been good starters in the transfer Bell and Summers, and in college football you do lose players every year. We have Robinson, Watkins and McAllister who have all played plenty, and a bunch of young pups who may help.
Lashlee's system goes nowhere without a QB who can run it. If we go into the season with a QB who I think can be an average AAC performer, I will be optimistic going into the season. But we don't know yet that such will be the case. If we are lining up on opening day with Williams, I will be rooting for the young man but I don't see how anyone can be confident.