I hear a song.
Improvisation is good. And what you have here is a very good sample of that. Though I think this can be made into a good song. Just take the parts that stand out from improvisation and make those into a song.
Hmm... maybe if I have time, I'll see if I can make a coherent song out of this improvisation you have here. I can definitely hear a song out of it. It's like a block of marble that is half carved into a statue roughly, and all it needs is the right vision and carving to bring it all out.
-HFX ^_^