It would be great to have the option to assign the expression pedal to different parameters on a per-scene basis, across all scenes, or even across multiple selected scenes.
For example:
Scene A: The expression pedal controls the wah.
Scene D: The expression pedal controls the delay feedback.
A multi-scene assignment option would also be very useful. For example:
Scenes A, C, and E: The expression pedal controls the wah.
Scenes D and H: The expression pedal controls the delay feedback.
This would provide much more flexibility when using the expression pedal in a single preset, allowing it to control different parameters depending on the scene.