Well said. Grip and managing your trigger are the big two in my opinion. New shooters, and some of the goofy instructors I witnessed, spent way too much time worrying about a perfect sight picture. I was always like "put that front thingy on that orange circle".
My favorite was a guy that would come teach a concealed carry class every week and spent a good 45 minutes yammering on about eye dominance. People would get on the line and I would have to make my way down going "don't put your thumb behind the slide" and "finger straight and off the trigger"...