Just in case anyone's interested, this is an *actual* rhapsody that 'Purple Rhapsody' has composed here: "a one-movement work that is episodic yet integrated, free-flowing in structure, featuring a range of highly contrasted moods, colour and tonality. An air of spontaneous inspiration and a sense of improvisation make it freer in form than a set of variations."
Highly effective use of the form!
I'm actually most intrigued by the live performance potential here. If there's any chance you can get the second pianist on board, one way to approach it would be as blending composition and improvisation.
Once both of you know the framework inside and out, you can start to take off on it, each one introducing a new wrinkle on the spot, and following the other's ideas as well.
This could be a VERY dramatic live duet!