I agree that sound/music adds a lot to a game, I will see if I could potentially add some down the line. Though as of now, I have no knowledge about any of it. Copyright, things like that.
Kevin Macleod has made a metric shit ton of royalty free music that anyone can use for any purpose. If you have a Youtube channel, look at the Youtube Audio Library, everything in there is royalty free creative commons licensed, if you find a song you like you can use it in anything.
