People familiar with musical notation might see a structural problem. An upright stem always originates from the right side of the head. If the stem points downward from the head, it always originates from the left side.
In other words, lowercase d’s and p’s are similar to musical notes, but b’s and q’s are backwards.
For those unfamiliar with musical notation, this might seem like a minor issue where artistic license overrules convention. But for those who read music, it might look like a mistake in the same sense that a backward letter would look wrong.
Aside from that, I like it. I don’t think it’s too simple, like you suggested. The way you’ve presented it is simple, but in actual use, that simplicity would help make it more legible against whatever might be surrounding it or behind it. When used as an app icon, the mark itself or its background could be dressed up a bit, but as the basic logo, simple is good.