I think Staley is outstanding as a DC but he's going to be the head coach now. So he can't spend all his time cooking up nasty recipes in the lab any more, he's gotta handle all the BS that goes on with the team.
Chargers have good defensive talent though. They have edge threat and they have good safeties. I think he'll have that defense playing very well in 2021. As to the whole team and gameday management and all that, I mean he watched McVay so he knows how it looks when it's right but yeah I think he might have some up and downs.
As to his defense this is a copycat league. Teams are tired of playing cover 3. Offenses have cover 3 down too. Double safety looks are gonna rise again because it kills the crossers that have terrorized cover 3. They just have to get a feel for how he schemes up the pre-snap change and run fills by the safeties.