@Felthry i've seen nb shortenings that are great in text (mx. and ind. (individual)) but none that work particularly well in voice. 'gentlefolk' works well for addressing a crowd, but not an individual.
@catterfly Mx. works quite well for a complement to Mr./Ms., but I was looking for something with the same formal tone as sir/madame.
Incidentally, I think Mx. works well in speech; you can pronounce it something like /mᵿks/ with a strongly reduced vowel, and just not worry about expanding it out to match the gendered forms.
@catterfly Liege I think is the gender-neutral form of Lord/Lady. Now I'm thinking about what the gender-neutral forms of all kinds of feudal ranks would be....