Even, as you’ve already noted, in more accepting times such as ancient Rome slurs like this were common. Julius Ceasar was apparently referred to as every woman’s man and every man’s woman in Seutonius. For having both an active bisexual sex-drive and apparently preferring the “bottom” role with guys, so what?
I think slurs like that then and now say more about the person uttering them than about who they are supposedly directed at. 
Ugh, I hate “dudebro” stuff and guys who have to paraphrase every interaction with a vaguely cute guy with “no homo bro, lulz!” Both in media and in real-life. Then again I can’t stand all Adam Sandler movies.
Well LGBTQ or not I tend to like it when cute “leading men” looking guys get used as the comic-relief, something that doesn’t happen enough.
Don’t worry I think you’re very queer @TSSL. 
Then again most of us around here are at least a little bit queer.
Still using the word does carry the implication that our attractions and preferences are odd, not the norm, deviant or unusual. Well okay some of mine probably are, but I refuse to be kink-shamed! 
Make the nonbinary form of address the formal and polite form. This game tried to be as gender-neutral with its society as possible, though it didn’t get very far, sadly enough.
Informally and with the RO’s however I would still like for them to acknowledge my mc as a desirable guy and vice versa, but that may naturally happen in a more informal setting. I think you can get away with making non-binary modes of address the formal and polite standard modes of address in your fictional society.