Nothing wrong with avoiding lifting heavy if you are satisfied with your size. At that point it's maintenance. Even professional body builders get devastating injuries, and if they get devastating injuries while doing a supervised squat with two spotters, then I don't trust myself to go for PR in the squat rack unless my form with the current weight is absolutely effortless. There isn't even a point for me to go for PR; I'm not getting a gold metal but I could end up with a hernia.