Thanks for all the great answers, folks! Really worthy, interesting and appreciated. In short, just a few notes -
@pixie you found the prior discussion of nets Nets Awesome!, and from the pics there I now see that bullets can be co-parallel with the wiring. Some tasty looking translucent shell (cubeoctahedron or higher poly shape perhaps?) might spice it up. @jeff 's reference to 10 x 30 nets from Ali Express Ali Express 300 LED Net shows them now at $240 including shipping. Worthy of consideration, but not “cheap” either. At the bottom of that listing page are several interesting arrays and net-like arrangements including Net-like Array and LED Array on Translucent Film.. This latter much like @gmcmicken filmed array Fairy Light Matrix on Clear Sheet, but his is better!
@gmcmicken, your matrix on a sheet is just really great. I love the whole approach… diffusion, effectively strain-relieving the strings, hot melt to clear sheet yielding wide angle viewing… that vinyl sheet though, did you see any puckering or melt behavior there? Could you reveal what type of sheet you used?
Finally, my fairly elementary observations about bottlenecks and such is that watching framerate behavior real-time is a great teacher and reality check for any given pattern/system combo. Multiple PBs and expansion boards can do a lot! Its not so difficult to wire this stuff up, as long as atention is paid to volts drop, and grounding grounding grounding That is IMO. Also there’s the alternative of running things from @zranger1’s ExpanderVerse, which opens up, well, yet another Verse.
ANd @Pixie thanks for running down the different Fairy Light strings. I have been running two types BrizLabs 200 LEd Fixed Address Strings and those 3-wire strings, where the data line hops back and forth. The former have much heavier wire then the latter. The 200 light strings seem to run fine without power injection, though there is some brightness drop.