I think it's dumb when cultivation systems for humans and non-humans are completely different without any justification. Like, why would snakes just keep getting bigger each time they got stronger, while humans stay the same size? Our bodies are basically the same, but humans, out zillions of different animals, are the only ones who cultivate in this one special way.
At the very least, whatever I write needs to make sense to me. If a bear can cultivate purely by eating random spirit plants in the forest, so can humans. If humans can cultivate by performing martial arts, so can other animals, assuming they're smart enough to learn them and their bodies are capable of performing the moves.
I do like having countless different cultivation paths and methods, but it should be based more on location than anything else. Basically, people will follow the cultivation paths their ancestors figured out. Inhabitants of World X could choose between cultivation methods A, B, and C, while inhabitants of World Y could choose between cultivation methods B, D, and E. If the inhabitants of the worlds interacted, pretty soon methods A through E would be available in both worlds.