Its not so much as that she is a terrible person. I don't mind that. If her being mean is the point the writer should go for that. Its a bigger issue of suspension of disbelief. If Dom Arona is stronger than you and is established as a threat to the village. And Sanders, the cumpire and Garth are sending you out to deal with it (despite the devs saying their all stronger than you, but for some reason can't solve their own problems) why would she join the party? Why should she leave the village alone? I don't have a problem with a character being a bad person or unlikeable. I have a problem with their motives not making sense in context to the story. Which is what I believe a lot people who point to dom arona being poorly written are getting at.
Using Moneymans example of Jack from mass effect 2. She goes along with Shepherd because she wants to get info on Cerberus and the fact that the prison shes in is about to explode. She's with you completely out of convenience, but as the series progresses genuinely comes to care for you and the rest of the crew (even Miranda) Same deal with Grunt. As grunt literally was going to kill Shepherd as soon as he got out of the tank. But joins as he respect Shepherd as a warrior. You can take either of these paths for Arona when she's a sub, but when she's a dom who has defeated you in combat it doesn't work. (It does work with a dom that you've throw the fight with, as once again it more roleplay, and less she's actually your dom.)
Arona's motives don't make sense. If she wants to use you as a sperm donor or broodmare, why party up with you and help if she's already proven she can just rape you? Why leave the village alone after she becomes chief? The natural progression should be her going raiding unchecked and building a harem of everyone in the village and slowly taking over the land. (or Sanders, cumpire, and Garth finally stepping up and showing us how strong they are. Or Kas stopping her and turning her into a demon general.)
I don't mind it being a bad end or separate thing. I just want it to make sense. Once again I do like her. I'd even say if written properly she could be more interesting than Brienne and Brint as she has some form of arc in her sub route. And is more than the warrior archetype that only fights, fucks, and sleeps. But it needs to make sense. And this is a constant problem in the game. A concept that on paper seems good, but is usually poorly executed. This is the reoccurring problem with almost every aspect of game. Its not me trying to be mean to the devs, but if they had an actual editor or someone on quality control so many of this minor issues would go away. But they just keep piling up.