Personally i saw one plucked string, im not seeing a lot of dropping your arm but i am seeing a bobble or two as you get to full draw, hold, let down about an inch, bring it back and release.
The crouched stance is ok - and good to practice for hunting, but you might find your draw shorter. Im not a fan of the open stance with the feet - in a hunting situation your not always gonna be able to line your toes up to the target and present the target as if your shooting for points. Your stance seems to work for you. I am not seeing follow through on your release that is your drawing hand coming back. Think of it as tension and then release the hand comes back slightly. Its used in target shooting, i taught it for years. BUT again, if you hitting a 6" cirle at 20 yards consistantly - the style your using is working for you - don't change it.
Over all i would say good form, decent drawing and shooting
Dave