Yes, this makes the translation to solo piano really well. It's such a nice piece. I wouldn't mind hearing the middle development section come around again, maybe after a modulation.
Gunther is suggesting an EQ change perhaps because it's sounding a bit thin? What it seemed to me is that the higher frequencies have been boosted, because it was sounding a bit metallic up in there. Could be that both of our responses are trying to pinpoint the same artifacts we're hearing. Did you do something maybe a bit extreme with EQ?
But back to the music, I really enjoy it. And with most things I enjoy, I feel a bit cheated that it doesn't go on longer.
Both the GPO and JABB pianos spike quickly when you increase velocity because of sample limitation so maybe that is what is being heard. They work best used with their libraries because they blend well and don't overpower the other instruments.
The Garritan Steinway will blow them out of the water for solo work.