This has to be one of the best ideas ever.

What I see is a great idea. I love the feeling, however, might I suggest more instruments:

Don't be afraid, but I can hear pizzicato strings (oh those are hot) playing to the beat, dancing the waltz. Now the strings are coming in. They are so expressive, they are wailing to the sad song. Only making the piano sadder. Oh, the flute, it's voice is so soft. It is telling the sad story. ALl is silent and listening to the piano solo...it is abrupt...it is not sweet at all, but it is not angry... it has lost it's life. It has loss the will to live, it died.

So those are how the instruments should be...ofcourse, I like this too, don't follow what other people say too much. Make it your own, though consider my suggestions as well.

And I know you said piano solo, but you can still make a "remix".

Good stuff.

you have quite the ear Harddrive, I would like to congratulate you for that, there are few with it.

I feel you should use a play on octaves here, you have a nice deep piano melody going, now if you add some high pitched piano notes, preferrably, a little faster then the low notes, to give it more "energetic" sadness.

I know you plan to use piano alone for many of your pieces, but then I must ask you to add more variety in the notes you put in the piano. It has a great beginning, but it could be much more.

However that is entirely up to you to decide, after all, you are the creator, and I am just the suggester ^^.

4/5 from me Harddrive, keep them coming ^^.