Improved (I think) the mutation method. It's incremental now - so
instead of totally repositioning, rotating, or recoloring a part, it
randomly adds or subtracts something from each of these properties. Also
I increased the gens per fixture and both mutation probabilities.
Just trying another slightly different approach... This time a smaller
population, and more generations before making fixtures. Also higher
mutation rates. Still not getting the results I really want, but hey.
It's getting there.