I like this concept a lot! I included it in my ProcJam compilation:

This is such a neat concept! I never thought of using evolutionary methods in this way before, but after playing around with both your project and PicBreeder I think I really like this way of exploring a function parameters' space.

I am not sure about how much more you can do/save with Pico8 but having a way to see a few of your previous choices to visualise the evolution you made would be nice :-)