You know what I think would be nice? An asexual, pan-romantic relationship arc. No Fade-To-Black scenes for people who are afraid of the jollies* and it represents a unique writing challenge, in that - while there might be an objective aesthetic appreciation - the wouldn't be any physical attraction and it would be far more about the character interaction, thus bringing (hopefully, at least) more interesting companion conversations.
That's something I've suggested for both Dragon Age III and Project Eternity.
I've also suggested an androgynous character. Maybe from a race similar to Mass Effect's Asari, but instead of being blatantly female they'd have characteristics associated with both men and women. Could be voiced by two voice actors simultaneously, or one with a voice that could be interpreted as either male or female.