Great suggestions! I've added the scale degree labels to the circle of fifths, text labels to the keyboard, and a root note selector. Now, pressing 'A' will always play the selected root note and highlight it at the top of the circle. I've also included a drone toggle to play a low root note in the background. This interactive visualizer should really help develop your ear and understanding of music theory. Let me know if you have any other ideas to enhance the learning experience!