It's an excellent piece of work!
Arguably, anything you may do with it now comes down to personal taste. It is well-recorded, and both piano and voice sound great. Where did you record it? I suspect you have put some hard work into your recording space
Anyway, if you want suggestions, there are some minor things I could mention (though I agree that you could just leave it as it is - this is according to my taste).
At times the balance between vocal and piano is great - the vocal is the main focus and the piano accompanies it. At others, the piano builds a little too much for my taste and becomes dominant, I would prefer the vocal not to have to "fight" the piano. It's just a minor adjustment.
What that does do for you though, is build some peaks and troughs into the song. In an ideal world, it would be great to add some other instruments to do that instead (with a light touch). I can hear some plaintive electric guitar, maybe some brass, backing vocals and some drums (maybe strings), especially around the chorus. Unless you have the musicians and the facility, however, I would leave that well alone.
Next, and purely a taste thing for me, but some of the lyrics are a little indistinct ("never knew love could be" .. what? It starts with an "s" and is the last word in the song). Most people won't give a damn though. If you want any comment on the lyrics, post them. To be honest, though, they seem fine.
These are nit-picky quibbles. If I could record something that good I would be over the moon
You know, this may not be what you want to hear (or maybe it is) but I think you have a really good commercial sound there, too. I could see a boy band using this song very successfully (£££). That is not a criticism!
Nicely done!