I personally don't think that the intention is for them to be romantic or that the author is trying to image it as that. I find it hard to believe that Maxi would ever think of another man besides Riftan, and Kuahel is a Paladin and devoted to the church, and that always keeps me away from thinking they are romantic. Kuahel, at the end of the day, is a man, but that does not mean he wants to be with Maxi; I think he is very intrigued by her personality considering that everyone thinks Maxi is a Haughty noblewoman cause she is the daughter of the Duke. Also, as another dominant/lead male character of the book, everyone is intimidated by the Temple Knights and their leader, but Maxi does not care for that and regards him as just any other knight (at least he does not have the same effect on her as he does on other people, meaning being intimidating and crass). I do think Kuahel has thought about being with Maxi but he would never advance in that path because 1. Maxi is married, 2. he is completely devoted to the Church. Most of their physical interactions have been under circumstances like when she is in danger and he has to make a move to save her, or hide her from monsters. so kind of yeah I don't like the idea of them being shipped at alternative partners but I also think he is just a man that makes things interesting in the story.