Hi, good well researched question! There’s no easy answer, but some hopefully promising directions.
Aurora can run on the Teensy 3.6, sorry it’s not easier to do so right now, but there’s info in here on how to get it to work: Too many errors compiling Aurora sketch
I just tried compiling the SmartMatrix Fadecandy port and it compiled to my surprise, not sure if it runs. It has worked on the Teensy 3.6 in the past. There might be some bit rot to clear after a number of years of no one that I know of running it. I do plan on really finishing up that port and getting it integrated into Fadecandy. I did just this last week put some work into a Teensy 4 Fadecandy port: [posted] SmartLED Shield for Teensy 4 - Drive RGB Matrix with 10k+ Pixels
ALA and PixelController I’m not that familiar with.
I’m going to be focusing on Fadecandy for streaming to LEDs over USB for my projects/products. With my Teensy 4 port, you can drive APA102 and HUB75 panels, and with the original Fadecandy Controller you can drive WS2812s.
Hope this gets you going in the right direction. Please post back with questions or updates!