it was a tad tongue in cheek, but I found his instruction on having the thumb over the bar and elbows back and closer to the body to help a lot with my squat, that and forcing knees out when going down. I don't push them any further up than what feels natural - I started reading his 60 page thesis on the squat in Starting Strength, but it all became too TL;DR! I disagreed mostly with the looking down part - I tried doing that vs looking up with the eyes and found that I was doing half good mornings!
Yeah his hip drive thing seems to be a bit controversial - I've seen a bit of bashing of it in PL circles. That said, some Olympic lifters don't like low bar at all.
I already have quite big quads relative to my arse, so not really concerned there, not really keen on front squats without a coach there to show me how to do them right, but I'd considered it. This might sound a bit strange, but I noticed more quad involvement from squatting barefoot vs wearing trainers (started to feel unstable at the 140kg+ mark).