Having just listened to this story, I find myself rather on the fence about it. Or, more accurately, I have a mixed reaction.
I was confused about the relationship between the retainer and the father. On the one hand, like Scattercat, I took the mother's words at the end, and the father's decision to follow in the retainer's footsteps, to mean that the two were lovers. I could reconcile that with his hatered of the women in the family, as he may well have resented them as competitors. But I could not have reconciled it with the breaking of the bowl - even if it was accidental, why did he send the daughter to do a task that (in his mind) inevitably would result in damnation for the father? He could have given her another bowl, even if that was less respectful. And it was clear he already had command of the household, regardless of the outcome of the ritual. The breaking of the bowl and the girl's ascent without it meant condemning her to death.
The only option I can see is that everyone in this thread is correct - he was the gay lover, but the father's love to him was one sided, and he was always a gold-digger. Once the father was gone, he seized the opportunity.
So then, I ended up seeing him as unmitigatingly evil. The rest of them - the mother, the father, the daughter, even the priests - seem to be far more understandable. They live in a screwed up society but are acting by its rules without deliberate malice. The daughter is a victim, but in this society, it seems women are trapped - they will be punished for obeying the rules, by being essentially slaves, and they will be punished for definace. The father, too, did not seem to me to be inherently evil - I don't think he had any choice about taking over his daughter's body, especially once the priests essentially sent her soul to the sea instead of his. He didn't seem to appreciate his daughter's sacrifice, but then he didn't seem to be able to do much about it, either.
So, basically, it seems this story is about how flawed characters in an opressive society. But I think it left too many threads too obscure to really make it relatable. I had to struggle to reconstruct the view of the story I detailed above, and it's clearly not what everyone came up with. And struggling to understand the story was a distraction from actually being able to empathize with the struggles depicted in it.