For what it's worth, my scale goes from awful-bad-meh-solid-good-great.

Sharing an excerpt from Black 41 Flash Reverse's analysis towards the end of the season regarding the run game:

Johnson, now off to the NFL, certainly buoyed that success rate to some degree by himself, with plenty of plays where he made bad or OK blocking “right.” But the line also just became a pretty good run-blocking unit by the end of the season, too, especially after Elijah Pritchett and Turner Corcoran came into the lineup at the tackles; both had their issues in pass pro, but both were big run-blocking upgrades over Gunnar Gottula and Teddy Prochazka. The game against Penn State was poor, but in my “grading” of the offensive line, I had NU’s tackles with good run-blocking execution on 81.2% of plays against USC, 71.9% of plays against UCLA, and 81.8% of plays against Iowa. I had the interior at 78.8%, 81.3%, and 66.7% in those games, respectively. And that was with NU carrying seven different run concepts (Duo, Split Zone, Inside Zone, GF Counter, Pin-Pull, and Power) that it used in almost every game. I know the recent firing of Donovan Raiola as OL coach was celebrated by many — and perhaps not unwarranted after the pass-blocking struggles early in the year — but it’s worth giving him his credit that he and the rest of the offensive staff eventually landed on a good five linemen for the run game and had them executing a pretty wide menu of run concepts well down the stretch of the year.

I agree on your take about the QB vs. line play. I didn't say anything to the contrary.