Shawnee, You are looking very good to my eye in these videos. You have really good shoulder to bow arm alignment at full draw and good string arm to arrow alignment. I'll make some suggestions here in a moment but there is no reason to not start grooving this in as you say.
These suggestions are really based on what I posted in my videos "rotational draw technique" and "release tips." So you may want to review those to see visual confirmation of what I try to say here. Again, I emphasize that these are suggestions only and that you have to decide if you like them or if they work for you.
If you watch your string wrist in your videos, when you start to draw, you have a tendency to let your hand angle out from a line through your forearm. Try to keep your hand in line with, or better inside, the line of the forearm. The arrow can point to the left of the target at the start of the draw and will come around as you reach anchor. Holding the arrow and hand in line with the target causes you to increase tension in the forearm that really isn't needed.
Now watch your drawing elbow's movement as you draw. You start high and the elbow comes around and slightly down which IS GOOD! However at the very end of the draw, you use your elbow to raise your string hand to your anchor. See how it comes sharply up at the end of the draw? I recommend that you try to not lift the elbow to drag your string hand to anchor but simply lift your hand to your references and leave the elbow alone. That little lift of the elbow will tend to disconnect you from the back and put you back into the top of the shoulder.
I understand clearly what you are saying about "moving in for sighting." BUT... one theory is that if you can "freeze" your spine and head position in the correct position before you start to draw, you will have a consistent frame of reference to structure the rest of your movement around. The idea is to bring the structure of your shot TO you rather than going to get it. I believe that you will find that you can still get the alignment you are concerned about without the head movement. Set your head position at the start of the draw and try not to let it move until the shot is over and the arrow is in the target.
As I say, you REALLY are looking good! The above suggestions may or may not help you and are relatively minor concerns. However if you try them, I believe that they will help.
Let us know how it is going from time to time.