We need to decide how/if to approach structuring the music. We could do a range of things.
No structure at all, let the harmony just noodle around with the soloist
Strict 16-bar, AABA format (where B modulates to the dominant), and each A/B lands on the appropriate end harmony
Some half-way house, where we invent some rules about what sort of structures make musical sense, but drive the final decision from the soloist's playing.
We need to decide how/if to approach structuring the music. We could do a range of things.