At the risk of looking like a troll with a romance post being my first to the forum...
I like romances in RPGs, but with a game like Pillars of Eternity the long-winded romantic discussions and cinematic cut scenes of sexual situations wouldn't work. I agree there should be something there, and probably the best way to achieve that is a bit of marked dialogue indicating interest, possibly a conversation about "...when this is all over," and then maybe an epilogue slide mentioning adventuring together or the characters finally pursuing their feelings. It really doesn't need to be more than that, but would still be enough to appeal to people who like a bit of romance to their entertainment. Any potential issue of representation can be avoided by picking two characters of each gender who would be sensible choices and making them available to everyone. Yes, that's the dreaded "playersexual" way of handling it, but again -- a game like this, you aren't delving that deep into things, and you don't really need to.
Having a bit of text to flavor things would enhance the story. No need to smack people upside the head with it.