just listened to the youtube video in the link. I like the ideas!
I did have a couple suggestions about the mix, I think the violin is getting a little buried, and the muffled piano might work better "sparkly" (for lack of a better term). Seems like there's some room in the higher frequency ranges you could use to let those speak more clearly.
The other thing about the violin is that the ends of notes seem a little abrupt, consider either lengthening those notes and fading them out in your DAW or do some dynamic phrasing if you're writing out in staff notation. You could also fake this effect a little by using some heavy reverb, but yeah the ends of those lines is a little dry.
That being said, really seems like you're hitting the ambient tone you're going for!