Put maybe some brass in it. Very mellow brass, french horn and the like.
I think you need to tone down the strings a LITTLE bit, they overpower the piano way too much. The strings, while sounding nice, should do a little bit more than play straight up chords on your next project... Things sound nicer that way.
I don't quite get the feel of an abandoned fish wharf through this song... It doesn't quite correlate with the description you've given. It's a nice song, but doesn't feel like it matches the subject matter.
As well, this ain't bad, just needs some polishing.
In my defence, a lot of music has been written in a very similar style. Martin O'Donnell comes to mind (Composer of the music for 'Halo'), John Adams, and Phillip Glass. All well known composers and even they will just take block chords and improvise above them. Even Nobou Uematsu uses chords with suspensions as sole pieces of music. I do need to bring the strings down however, they are not just playing 'straight up chords' as there is movement. It is just very subtle.
Please contact me if you would like to use this in a project. We can discuss the details.