I have some thoughts on your post...
1) Sullivan's QB skills aren't the best thing he brings to this team. How people can't get that through their heads is baffling.
Brendan Sullivan opens the field up and completely changes defenses' plans and abilities. You heard it from Kaleb Johnson's mouth in the post game...they asked him what changed from the time he was getting devoured in an 8 man box to the time he ran for over 100 yards and 3 TDs and he answered that the field was more open, lineman could block one on one, and he had holes open up where he could get to the next level and use his feet. Johnson is the best player on this team by light years. But if he doesn't have anywhere to run what do you want him to do??? Sullivan allows him the space to get where he can use his skills instead of collapsing 3 yards behind the LOS because teams know CM can't make even simple passes once he gets pressured.
Cade McNamara checks his first read, if it's not there the pocket is by then collapsing and he has two choices, neither of which is good. a. turtle up and bear hug that ball so you don't fumble it when you inevitably get sacked, or 2. make a really dumb throw into man coverage. Which is double bad because he struggles to even hit wide open receivers when he's not pressured.
How can you think about a couple ill-advised passes and not give even a little bit of credence to the way his being out their allows our best player to do his job?
B) Sullivan electrifies this team and electrifies Kinnick. You know how many years since Ricky/Drew/CJ we've had QBs who soiled their underoos at the first sign of "oh shit?" You could see it on the team when he came in and started turning sacks into 7 yard gains, throwing blocks out in FRONT of the ball carrier, chirping the other team when he got trucked out of bounds...the rest of the team was juiced and it changed the whole environment in that stadium, both on the field and in the stands. It was a total breath of fresh air and felt like the good old days when we had badasses for quarterbacks.
Those are things the trinity of RDC did when they were here and it's what this team needs. CJ Beathard in 2016 was completely beat to shit and running on pure adrenaline by the end of the year but he never once got scared and he just kept on taking the punishment and putting yards in the book.
We need moxie. We need another Rick/Drew/CJ. QBs who are really nice guys, super smart, and great locker room dudes aren't enough. Nate, Spencer, and Cade are great guys and good leaders I have no doubt. But they don't have that dawg in 'em. WE NEED A DAWG. Period.
When it comes to quarterbacks and other true leaders of teams, ask your self this...which group would you rather go into armed, real-life military combat with??? Actual bullets flying and bombs exploding...
Are you going in there with Rudock, Nate, Petras, and McNamara, or are you going int with Drew, Ricky, CJ, and Sullivan?
I'm not asking you who you want to be your son's football coach or marry your daughter, or manage your retirement investments...I'm asking which of those two groups are you gonna go to war with and try to survive? Stats or not there's your answer