my initial thought is that there needs to be an increase in the overall volume of the project.
the arrangement is fantastic, you've got your own spin on the melody in there as well as enough of the original to pass by here...
the delay usage seems weird to me. i feel this way because if it's a "live" solo piano mix there isn't going to be that kind of delay. i know there was some used in the original song, but it just feels weird to have that many echoes when it's supposed to be a live track. maybe take it down to just one or two softer echoes. i can see one or two being actually playable in there.
i'm not sure how i like the unresolved ending.
also because this song doesn't go very much into the low end of things, maybe bring this out to have a stronger effect (especially at the end).
these are pretty nitpicky comments to be honest, the main thing you need to address is volume.