I like to feel atletic position, feet anchored into the ground and yet a springy feeling in my legs. My back is fairly straight, my shoulders are square and back versus slumped, and my arms just hang from my shoulders naturally.
When I swing my club, I feel as if I could go 75% or 90% or 110% and never lose my spine angle or balance.
I like to feel as if my head and neck are there relatively rigid and my upper body pivots around them.
My lower body is anchored into the ground and my hips just turn naturally as far as they need to to support the large upper body pivot.
When I transition, I feel like a giant coil that has been wound up is just unwinding without any more effort than to allow the unwinding.
I trust my swing, I trust my alignment, I don't really have to wonder where the ball is going, I know-most of the time.
After 45 years of playing and teaching, these things are second nature.