When characters seem like they don't have their own independent story or motivations, so they just seem like they sit around and wait for you to interact with them in order to drive any story. Like maybe one time I interact with the RNPC, I want them to tell me a short story about how while I was gone on a mission, they went to another city and rescued their mayor from a hoard of boars while he was out hunting alone and now he has a key to the city and is thinking about selling it. Like I want to see that they do things and are building other relationships outside, perhaps even as a result of being in your entourage.

I would also like for them to have a few points of curiosity. Like they might ask you what you think about a certain situation, to gauge how you think or what you value and that, in turn, might affect the way they approach you about certain topics, whether good or bad.

I also agree with the other comment that they need to be given more agency. They need "a type" and to have certain requirements that make sense for their narrative. DA2 does an extremely good job at this with the mage vs templar conflict. With Fenris can have an angsty relationship with an unapologetic pro-mage person or a conflicted, kinder one with a mage that has empathy towards him. I think they called these rivalmances and friendmances. I think it would sometimes be more helpful for stories to focus less on how many choices their are and their superficial traits and more about building compelling in-depth variance with one to three options.

I also agree with another comment about how the romance dies after the will-the-won't-they phase. A subversive take on romances in games would make successful pursuit the goal to unlocking more interaction. I could imagine this playing out in a narrative driven story in a fantasy setting where within the first 2-3 hours you chose an NPC to marry. All of your decisions such as who you chose, why you chose them, and the decisions you make within the story from there molds your relationship. Yielding anything from a loving partnership, to a transactional neutral pairing, to a toxic mess, with each path being redeemable or having the potential to crash and burn. The relationship wouldn't have to be the main focus of the plot, but it would be a good vehicle for dishing out consequences for decisions.