It doesn't need to be an outright relationship or eb. Just let us bond with the NPCs by giving us quests to hang out with them, fully voiced with long cutscenes and descissions we have to take. That way we actually care for them.

Maybe a questchain where we get wasted with Thancred, trying to hit on fair maidens and failing miserably, ending with a scene of our character and him strumbling drunk through the backstreets of Ul'Dah. Could even get it a little more serious with him breaking down because of Minfillia and you having to console him.

Or get a quest from Matoya, telling us to distract Y'shtola from her work, ending up in Gold Saucer, able to do mini games with her. She has such a competetive side that she would maybe give us a run for our money.

Or training with Lyse, or having to mediate some sibling squabbelt between Alphinaude and Alisae or... the possibilities are endless.

I know it would cost money for voice acting and require a lot of work for something that is not a gear threadmil, resulting in sub money, but it would feel so Final Fantasy to actually do stuff with our companions for once that isn't saving the world.