I think that the Bible gives the impression that Mary was willing to
be the mother of the Messiah not because she feared God's wrath but
because she genuinely (if wrongly) believed God was good and that His
actions were all for the best. God's impregnation of Mary seems to
me to be like the action of a doctor who carries out an injection of
his sperm into a woman's body, where the woman does not mind, the
doctor possibly knows the woman does not mind but he still does not
formally gain her consent. The Bible does not acknowledge that there
is an issue of consent, taking it for granted that everyone should go
along with God's will. So although God is perhaps being unethical I
would not consider Mary's impregnation to be an atrocity.

Unlike the other actions of the Biblical God. The killing of the
Egyptian first born, the plagues visited on the Egyptians as well as
certain other acts seem to me straightforward atrocities.