Regardless of gender, orientation or any other aspect of the character, their handling of themselves should be the result of who they are as a character. Their personality, individual wants and experience contrasted by or mingled with those of their culture or religion or what have you - anything really. Never should such things be dictated by concepts such as being a beacon or statue to some ideal, unless they themselves are attempting to be said ideal, and even then, Humans, and thus one assumes non-Human sentients, are flawed. Even when we strive for an ideal, we rarely reach such heights, only scratch upon them, maybe haphazardly scramble upon in the best of cases.
Essentially whatever is on show, should be representative of a given character first, never an outside ideal, and their own ideals, while on show, shouldn't be perfect and flawless things. We are who we are, but the disappointment or praise of others is nothing compared to what we often put upon ourselves. That extends to concepts like loyalty, disloyalty, promiscuity and all other manner of such things you might imagine.
One might wish to indulge and enjoy themselves, be promiscuous, but experience attachment too easily making that freeform lifestyle impossible. Some people fall in love over nothing. The reverse is also true, some people find falling in love near impossible, and find little but temporary comforts. These are but two examples of the near infinite, countless, ways in which a person might conduct themselves and be challenged by their own nature, and only in reference to love and sex, when our experiences go well, well beyond love and sex.
I think, most importantly, I want layers from characters. I obviously speak for no one but myself, in all of what I've said, but many different and multi-faceted characters is a good thing, but I'm not drawn to stories and characters by the fantasies of ideologues. I've never encountered such fantasies. Fantastic characters must still be believable and relateable as actual, layered and flawed people that, like most actual people, something that doesn't make them bad people. Flaws are a natural result of sentient, mortal, life . . . amongst many other things.
I'm also quite fond of characters that are, who they are, despite encountering a protagonist. In BG that meant they could leave you, if their morals conflicted with yours too harshly. I think this works for me in orientation as well. I'm not much for player-sexual NPCs. At the same time, I don't think there should be something for everyone, at least not in an obvious way. Imagine with me, for a second, if you could define, through dialogue, your characters as a particular orientation. Maybe it's something others know, maybe it isn't. Now imagine being in a new galaxy and finding . . . no one shares that interest, at least no one that's available.
One thing that romances in games often fail to address is loneliness, and how a characters deals with that. With the amount of people, via size of the ship, being brought to Andromeda, it seems unlikely there won't be another of a given orientation, but it's something to think about. Too many game stories have interpreted loneliness as something that happens when you're alone, truly, often in environments devoid of other life. There's something to be said for exploring a character being alone when others are around.
I think the ME series actually tried to do a bit of this, in my third play through, that tried to remain mostly Neutral throughout the series. Where others might have a romantic interest, or a picture of their lover or what have you, this third character at a quiet time with dire events impending . . . was alone.
It's one of my favorite scenes, in a way. People get so caught up in romances, that they often forget that sometimes you end up alone, even if there are other people around. It's worth exploring a lone sole play through, and I'm curious if there will be another quiet moment, or something they actually build upon this time around.