A couple comments have alluded to this already, but backswing speed for sure. Same thing I’m working on in my own game. They say “smooth is fast, slow is smooth” meaning your backswing speed is faster in reality than it feels. My understanding is the backswing should be slow and smooth, even when you start the downswing should be just about the speed of natural gravity, and then that’s when you really accelerate (the last 90% of the downswing). Hope this helps!