It was pretty magical when it all came together, and I completely get what you mean by the pianist “leaning in”. If I don’t misremember, the top fast moving part that’s kind of like an arp but a bit more complex is a rhodes soundfonts where the louder velocity layers are a bit distorted and the lower velocity layers are super smooth. I play with the velocity throughout the track, and that’s what gives it that motion. I absolutely adore it, it’s the kind of attention I couldn’t give my notes before, but now when I’m working with soundfonts it’s just comes a lot more naturally to sit and fiddle with small velocity changes and automations. And my tracks sound a lot more alive thanks to it I think. Thank you for trying it!