Disklavier

Hello Fred

Reading your question I cannot really help you for changing the midi file specs, but as someone suggested re recording it at a lower speed can help to put special attention on the way ones touch the keys and thus maybe reducing the harshness... but playing slower has also its drawback since if your not too good with tempo you can drag into outer space... But if succeeded a slo tempo file that is then speeded up can sound very convincing (not always though).

Once anyway you have your midi file I wouldn't waste any time in trying to make an audio recording of your piano (indeed you need to take so many parapeters in question its a long process UNLESS you youd like to learn that... then its a good way to start). That was fine 20 years ago but now if you have access to a decent computer equiped with a sequencer that houses a sampled (Garritan, Pianoteq, or even no name samples since your not trying to create an orchestral sound but the one of a piano which is kind of simpler to achieve) piano I would say that is the way to go. It permits you to tailor the sound that you like and then add some reverb etc... when its nice you burn it in a Aiff file or cd and its done... and you listen after a couple days and you improve a bit (not always!)

Hope this little bit helps