Long story short: Found a kaleidoscope shader (by Trixelized, Godot Shaders) as a starting point to get things going, edited it, initially set up a completely randomized version (so every puzzle/layer anyone did was entirely unique), made matching work, then pivoted to using the randomization version I made to generate sprites I liked so I could actually have set levels/progression.
Hoping that makes sense? Haha thanks for playing and vibing!