Some good ideas but you have a lot to learn. (I like the filming of the reflection of the hands playing, but definitely get a tripod.) It would appear you are probably just beginning, so keep posting videos and accepting feedback. I am not anywhere near an expert, but if you are serious about video editing look into classes or look for indie movies that are wanting help behind the scenes with no previous experience necessary. (If anyone has more video/film experience feel free to correct/edit anything I say.)
My avatar is a reminder to myself. I need lots of reminders...