Travis Frederick definitely hurts the overall strength of the starting 5 OL, but I really like the overall depth there.
Tyron Smith & Zack Martin are still elite.
La'el Collins is closing in on Pro Bowl caliber.
Connor Williams is still young (23) and has potential to get better.
Joe Looney is serviceable.
Connor McGovern (22) is going to be good IMO.
Tyler Biadasz (21) could be a future starting Center.
Cameron Erving has good size, is still relatively young (27), and has 42 career starts.
The position flex is legit for once here. Williams could play (and probably belongs at) Tackle. McGovern can play C or G. Looney and Biadasz could play G if needed. Erving can play G or T. The quality and versatility of those 8 gives the team some options to run short on OL if they like their depth at other positions or want to keep a talented young player (Jelks, Westry) without exposing them to the Practice Squad. It's also why I wouldn't be afraid to include a Connor Williams in any package to acquire a certain All Pro Strong Safety.
I also want to see how the International player Isaac Alarcon from Mexico works out. Only 21, he's 6'6" and 320 lbs. and is about to be exposed to elite-level coaching and competition for the first time in his life. As an International player, he's roster exempt so the team doesn't have to keep him on the 53 (or 55) right away.
However, I do think Brandon Knight and Adam Redmond are Will McClay slash Fan Zone legends which typically amount to be no-name JAGS that people like to pretend are diamonds in the rough.