@ShawnE : OK, good. You're making very good progress, and you'll find, as we all do, that progress can be appreciated in steps, or plateaux. You'll think that nothing's happening, until suddenly it happens, and you realise that you've progressed. This is where the Patience part kicks in; one has to continue to do the mundane, daily routines, assiduously, in the certain knowledge that it all pays off, and handsomely, and faster than one thinks..! One little test to do every now and again (three months or so..?) is to turn the guitar round, and try to play the exercises left-handed (or right-handed, for lefties...). That's the level of control you had at the very beginning. Now turn it back to your normal playing fashion and appreciate the difference..!
One more little thing (well, not so little, really...), concerning the right hand, or rather, the right arm. Swinging the arm up and down, strumming with a piston movement, is a technique that's useful for some styles of playing, but it's not really conducive to good right-hand technique. Can you try relaxing the right arm completely, and using a wrist movement instead..? A relaxed hand and wrist, too; just enough effort to have the pick brush the strings. Adjusting the force of this brushing is what gives life to the strumming, with only very slight effort, so it's not tiring. Light, measured strokes, with a relaxed arm, will bring much benefit. The swinging piston can come later, if context calls for it; a more delicate approach allows the music to come through for most playing, though. Worth trying..?
In any case, keep it up; you're doing very well, and the videos are very useful, for us to see what you're doing, and certainly for others treading the same path. Good Stuff.