If one’s goal is to consider and perhaps identify the presence of some patterns common to and / or characteristic of a “really good laser number”, then one could inspect the number Rocky Mountain Way from Laserock II for structural devices that might suggest more generally applicable patterns.
(1) The choreography of the visuals emerges from, and thus naturally follows, the structure of the song. This song structure follows the familiar form of verse, verse, break, verse. Also to note, a novel sonic element (sequencer, talk box, etc.) is featured in the break section. The summary, or closing verse brings a sense of triumph in musical completeness, which is successfully expressed visually through the bringing together of previously introduced elements.
This song structure is also evident in numbers including Turn Me On, Hyper Gamma Spaces, and Red.
(2) The imagery is minimal in that it is a small number of graphical forms being used in a variety of ways. By virtue of that minimalism, an abstract musical and visual narrative is successfully developed, and with that comes a rare humor unique to laser shows. The humor lies in the recognition that a reference to, or a representation of, a specific thing or concept is being made in a medium (or at least a presentation) that has defined itself as being fundamentally non-representational.
For example, the visual narrative in this piece could be interpreted as follows: Signal from AM rock and roll station is heard on car radio, and the spirit of physics appears and speaks of bouncing around on the Rock-y (meaning rock-and-roll-ish oscilloscope display) Mountains of music.
Another song structure that works well for supporting an abstract visual narrative is “before and after”, where the first part of the song is a melodic incantation and buildup leading to a turning point, and is followed by a transition into a second and musically different second part.
This song structure is evident in numbers including Lunar Sea, Silk Aurora, Phobos And Deimos Go to Mars, the segment of Awaken used in Starship, and is also obvious in the songs One Of These Days and Careful With That Axe Eugene.
Valid objections to the digital clunkiness intrinsic in frame based output and multiplexing notwithstanding, an excerpt comprising some of what I remember of the original choreography of the ending of Rocky Mountain Way may be found here:
https://www.youtube.com/watch?v=jSxnnsbQnqs
On a technical note: Anyone care to comment on the use of external audio signals in the 6b? I think maybe the number "The Wait" used external audio in some way.