The reason why
I think the reason why you cant expand on this is because it is 10/10 in its own right as a piano melody, that's just what this is, it doesn't need more to it anything more and it would take away from the inherent beauty of it.
I mean sure you could use it and change it and i mean I'm even working on a slow rock style love song that this would fit nicely into but i mean i don't want to ruin it, its great just the way it is, don't expand on it don't change it just admire it.
Honestly i mean i do art at college and i know a bit about overworking something until its past perfect and goes full circle back to sh*t so please don't do that to this it would be a shame and a real loss.
Its going on my ipod dude, you rock :)