Any particular pet peeves occur to you as a writer and reader? If so, what are they and how serious are they to you? For me, a major one is when are a poly guy somehow abruptly adopts a monogamous lifestyle without any clear reason, simply because the writer thinks that this is the only stable arrangement for the long run.
Another is whenever one person of either sex meekly accepts a double standard imposed on them for any reason and does nothing to assert principles of basic fairness and justice or seek vengeance.
As Saturninus commented in Titus Andronicus, "What, Be dishonored openly and basely put it up without revenge?" The Bard summed up very accurately the pagan ethos of vengeance as noble and a moral virtue instead of a vice, as the Christian ethic would assume, quite well done given his own Christian prejudices.