You know what never moves? The plate. Rather than using two continually moving targets, why not start with the one constant in this equation. Find a good stance based on the plate. Then, fine tune it based on your moving pieces.
I find it much harder to call pitches when I can't see it cleanly out of the pitcher's hand. If I have to find it somewhere mid-flight, it's harder. So, we'll have to disagree on most of your points. Different people, different styles. Good luck.