I'm not a fan of SS low bar-head down squatting technique at all. My daughters are both nationally ranked Olympic weightlifters and very few elite lifters squat like this. I think this is more accepted with power lifters. I lifted with my girls in the past and competed a couple times in the Master's class (I'm 49) and played high school sports and college football. I never lifted with good form until I started with an excellent Olympic weightlifting coach. We execute high bar-head straight/up technique and ALWAYS squat below parallel.
I like
Loo.wii's advice, and would add some cleans and snatches into this routine. For older less flexible folks, stick to power cleans and power snatch until you loosen up and master the technique. It will take some time, but once you have these lifts down, there's little need for additional cardio if you get after it.
In between lifting days do some walking, rucking, etc..., to work out soreness and stay loose.