When it comes to Athena's birth from Zeus's head there are actually two versions. In one version there once was a mother involved, Metis, and in the other version Zeus created Athena on his own. The latter seems to have been the most common during antiquity (the ancient Greeks liked to think that women weren't really useful for anything, not even for having kids).
The Metis version was told by Hesiod. He says that Zeus made Metis his first wife, and then he lists Themis, Eurynome, Demeter, Mnemosyne and even Leto as wives or lovers of Zeus before he mentions Hera. When he then tells about Athena's birth, it says that Hera became angry and as a revenge gave birth to Hephaestus without a union with any man. So first we hear that Metis was Zeus's first wife, but then he says that Athena was born when Hera was queen of Olympus. Is it two different versions that Hesiod puts together in the same story? Or does it mean that Athena was inside Zeus's head for quite long and didn't come out until he was married to Hera (that's obviously how it happened in this comic anyway. So in case there is any confusion about this, Athena is not the result of adultery. That is why Hera accepts her into the family quite easy. But she's very upset that Zeus hasn't been more open with her)?
Given that the content of your comic until now seems relatable, today's sexism is still strong, just less obvious.