I don’t know exactly how you can get that leaf venation pattern but attached is an example of using anenome to do branching.
It randomly creates and destroys branches. You might be able to figure out how to apply this to a 2d leaf venation pattern. I’ve tried in the past but never managed to get it. There have been a few examples on this forum and the old forum if you search.
AnenomeGrowth.gh (30.6 KB)
This is interesting too…
https://discourse.mcneel.com/t/huge-circular-victoria-amazonica-lilly-leaf-pattern/130987