I'm always happy to see L-Systems! I find them really awesome, the base principle is very simple: string rewriting. But the results can really be impressive for such a simple concept.

I can't help but do a shameless self-plug: I'm developing an interactive L-System generator : https://github.com/epholys/procgen.

Here is a little demo: https://www.reddit.com/r/proceduralgeneration/comments/b4kpa...

And here are the L-System I've produced: https://imgur.com/a/0Rx7uln