Well, in all honesty I suggest working with a pianist. He/She will be able to get the right vibe out of the piano with the click of a finger. Playing softer and harder, accenting notes, not playing 1,2,3,4 chords or basic chord progressions. Basically breathing soul into the production.
If you do not want to do that, no worries. You just need to understand how and why a pianist plays a certain way. For this you need theory. I suggest you start via looking at Julian Bradely and suggest reharmonization as a start. Also understand you need chord progressions that can vary rhythmically even between notes.
or spend 10 minutes with a pianist :)