Nice!! I had a lot of fun with a project like this with some more generalized rulesets. This video got the most views: https://www.youtube.com/watch?v=EW9Q0qMc2Xc (just running 3d Brian's Brain) but I like this one the most, with a much more general ruleset: https://www.youtube.com/watch?v=SoJvS6GuM3c&t=90s

The code is here: https://github.com/heyitsguay/gol3d

I keep meaning to go back and create an automated ruleset explorer that looks for stable but non-oscillating and non-constant population counts. Maybe someday...