[Daryl]

This is the portion that is very confusing to me because my hands and pp#3 travel down the TSP to impact while the sweet spot of the clubhead comes down the elbow plane, and usually drops below it right before impact.

What should be fixed, the hands need to get lower to the elbow plane? or the club needs to be swing "out" more to get on the TSP?

This is a "way of looking at things" problem.

The "#3 PP" and "Sweetspot-of-the-Clubhead" are the Plane. They define the Plane of the moving Golf Club. The Elbow and TS Plane are reference points only.

The solution is not to swing on one Plane or the other. The solution is to have the #3 PP and Clubhead swing on the same Plane throughout the Swing. The goal is to use the same Plane from Top to Follow-through and beyond.

It does not sound like this is your problem. It sounds like your Clubhead and #3 PP are on the same plane. It sounds like your Plane has rotated to the Right and you are swinging severely inside-out, across the line: an Inside-Out Stroke. I could be wrong, but it sounds like that to me.