@caisson: The idea came to my mind also. There is a control for scaling jitter and for rotation jitter, so no idea why not some form of movement jitter would be possible. I tried to fool the script by moving the origin of my prop and force movement via rotation, but no avail.

Reducing the polygons of the scatter plane does not change the positions of vertices, it only takes some out, so your rows will still be there but be incomplete. The difference wit the full mesh may not be that large.

The good old Poser deformers (magnet, wave) and morph brush may be more effective to break alignment. You can also do the scatter in a few steps, say use five passes of 10 instances instead of one of 50 instances, and move, scale or rotate the scatter plane between the passes. The scatter plane is only used to give xyz coordinates and normal direction during the scatter action. There is no further connection between the grouping and the scatter plane. Alternatively move the grouping.

Now that I think of it, the current setup may not be that restrictive.