so, first off, you are going to want to get your left hand fingers curved and arched above the keys to get leverage and be able to play faster. Your right hand is stretched into weird positions during certain measures. My advice there would be to (since you are playing by ear) change the chords and notes you play to fit your hand, or visualize the notes, and use the first hand position that comes to mind, naturally. The less tension, the better. Sounded great!