I am comfortable with three of the spots being Paris, Adams, and Fro. I have no issue with a starting OG spot being Adams to lose. I do think it will be a challenge to add a starting RT of Williams quality(depends on Jonah of course), a swing OT (maybe the same as the starter), a replacement OG who is better than Hernandez, and a reserve interior OL better than Colon and Adams last year.
Not saying it can't be done, but it's gonna take some work for sure.
You could re-sign Brown and have him as backup G/C. In fact I think they may well do this. Christian Jones might fill the swing tackle spot. He played LT at Texas, played RT in limited snaps last year. He only played 70 odd snaps but had a 77 pass block grade. He could be the answer.
Hernandez wants to come back, there's a test here for Monti on how much he wants to pay him. I expect him to test the market.
The big Q is Williams. If Williams is going to miss games does that make it more likely Beachum comes back? And if he does does he use that to get more money out of Monti? I would.