Problem here is for as far as I am aware, that old age and death are not a dependency for Unknowing/Ignorance (as explained by Ajahn Brahmali, Bhante Sujato and Bhikkhu Sunyo in the workshops of Dependent Origination).
Also, I am not sure whether for example, Dukkha is always a result of old age and death, that would make it causality. For as far as I understand, Dukkha is dependent on old age and death, not caused by old age and death.
In any case, muddling on in Saṃsara, here is the result for now using PlantUML:
Again, I feel like we are mixing different types of states. Ignorance is a mental state, old age and death is a physical state.
I don’t read DO as a dependency diagram (despite me drawing it in Mermaid as a state diagram) but as “one thing inevitably leads to another”.
So Upādāna leads to existence (in other words, our craving leads to us becoming, or continuation of existence, which then inevitably leads to birth, old age, death etc. If we did not have craving, we would be free from the cycle of existence.
Certainly don’t disagree that without craving (which is dependent on ignorance), we would be free from the cycle of existence. Only notion I made is that old age and death does not form a dependency of ignorance (so the back-arrow was what I was pointing at )
In any case, I finally found a way to consider Dukkha as a result in my diagram, and I removed unnecessary complexity.
By the way, the while loop of Avijjā could be understood as Saṃsara, maybe should annotate that.
Again, I use the “inevitably leads to” to interpret it as “old age and death” inevitably leads to “ignorance”, as rebirth effectively is starting again, so whatever we have learnt will be forgotten, ie. “ignorance.” Of course, this is playing with words, but I think there is a core essence in there that feels true.
BTW, have you thought of modelling DO as a sequence diagram, with the factors playing the role of actors? You’ll have to think through what is the “message” that is being passed across the actors. You may find the exercise insightful.