I think it's helpful to identify WHY the ball is going shorter when making a swing change. Is it from different contact? Slower speed? More loft/spin? etc. If you can't figure that out, that's not the end of the world, but if you know that answer, it can help with confidence that you know you're working on the right things.
Everyone is a little different, so I'm cautious about rushing someone to move on to a complimentary piece. But I would probably start working on getting the arms a little shallower at impact. That would help with the low flight and potential to hit pull shots. It also might help with some of the distance loss if due to speed. At this point, you can test to see if you can add a secondary focus without losing the pivot training you've done.
If you're up for that, then check out the "don't break my arms" and "Moe norman arm drill". Looking at your video, I'm not sure if it's driven by the right or left arm, but it's worth investigating both.
Good work so far,
Tyler
PS - Don't worry about the squat/deadlift realization. I've had many instances I thought I was doing an exercise cleanly only to learn with training that there was a fair amount of room for improvement!