I like the minimalist visuals, and the progressive music concept. However, that last part needs some work, because as it is, it's not really pleasant to hear. Plain sine wave just sounds like a phone dial! One suggestion I could make is experimenting with stretched sounds and slowly changing effects (such as bass filter or additional instruments). It's a nice way to compose with sustained notes, yet making them evolve so that the music feels flowing.
Still an interesting concept, very accessible and with potential. Good job!