Our common law legal system does a pretty good job of that already. For example:
> Threatening behaviour included or excluded?
See the legal definition of assault.
> "Likely to cause harm" or "intending to cause harm" included or excluded.
"Likely" is excluded in common law if that's all you have, because, as I said in response to another post upthread, actual facts trump guesses. "Intending" falls under assault if, roughly, the intent is perceived by the target.
> Is running off the road OK if no material harm?
Again, see the legal definition of assault.
> What if they have a heart attack 20min later due to stress?
How would you prove, in a legally sufficient sense, that the heart attack was due to whatever happened 20 min earlier?
I'm not proposing "caused actual harm" as the standard because I just made it up. I'm proposing it because it is the standard that our common law legal system has used for the vast majority of its history. It's only fairly recently that nanny state legislators started thinking (incorrectly, in my view) that they were smarter than centuries of common law jurisprudence.
Is running off the road OK if no material harm?
What if they have a heart attack 20min later due to stress?