You would be in a better position to notice common fallacies etc, but any "list of logical fallacies" is a good starting point, especially those fallacies that can be used to insult, or insinuate, E.g. Specific guidelines about ad-homs. This would also include advice
not to use personal information/ circumstances in an argument, unless you are happy to see them criticised.
One of the worst fallacies, us probably the kind that removed the civility from a discussion, and hence the good faith.
As a side note, the worst kinds of guideline is an ambiguous one, that leaves a lot to interpretation, e.g "act civil" is itself a nice rule, but otherwise useless, better off as a heading above specific clarifications.
HN doesn't need to be Wikipedia wrt comment rules, but a few Wikipedia style rules might be good.