Biggest concern is DC Sean Desai. Other than being some sort of defensive coach for football powerhouse Temple for 4 years in the mid 2000's, he has had nothing to do with actually coaching defense and has been little more than a pencil pusher and and film guy until 2019 when the Bears promoted him to, not even DB coach, but Safeties coach. Two season later he is the Bears DC.
Hope they catch lightening in the bottle with him but he went from a 30k-50k peon job to DC in 2 years all while coaching a position with the Bears where EJ went from PB'er to shit under his watch.
I doubt you will find a weaker resume for an NFL DC. His hiring was more about no qualified candidate wanting to jump on the Nagy shit train to torpedo their career path than Desai's acumen.
His position was basically that of a glorified PFF volunteer.
Contemporary coaches are always searching for an edge over their opponents. Now that the Computer Age is upon us, the analyzing has become more technical. Many of those coaches have assistants called the "Quality Control Coach." However, the QCC doesn't really do much coaching at all. They spend all day multitasking, breaking down film up to five weeks in advance and analyzing data.