Just as a heads up, the adjustment of putting your heels on a 5lb plate is actually used to train depth in the squat. "Ass-to-grass" is the squat standard for weightlifting (i.e., like in a 3rd world squat, you should want to be able to sit down on your heels comfortably), and the idea is that squatting a bit higher weights than you can do without the heels elevated with the heels elevated trains that depth in the movement. Point being, eventually you might be able to get to just under parallel if you keep working on the heel-elevated squats!
Also, re toes slightly out, this is how you should squat, you shouldn't square up with the rack or keep your feet parallel, because (again, referencing the 3rd world squat) if you were to sit down on your heels, mobility permitting, you would basically have to have your toes slightly outward.
Also, re toes slightly out, this is how you should squat, you shouldn't square up with the rack or keep your feet parallel, because (again, referencing the 3rd world squat) if you were to sit down on your heels, mobility permitting, you would basically have to have your toes slightly outward.