I re-read this entire thread and it really opened my eyes on a lot of things. I need to try to get that 1 minute for the glute iso holds and see what happens. My calves usually start to cramp after 20s though - but I will definitely focus on trying to get to 1 minute while maintaining maximum glute contraction for the entire duration of the set.
I'll also give that 3-bounce full to parallel squat for VMO development thing a try.
Thanks again.