I love the shapes!
Really, the shape of this piece is so nice... it's like you're always reaching higher but you can't really get there... it's quite beautiful. Whenever I improvise on the piano, I just go insane and become either hectic or inappropriate, so I congradulate you, sir.
Also, improvising with your eyes closed should be the only way to improvise. Especially for someone like you, who just learned by ear, which I wish i had... it makes it so much more intuitive. Excellent work, my friend.