Well, in troll canon, asexuality has different problems, because failure to do your reproductive duty for the Empress when required is punishable by death (and this is a major driving factor in troll romance.) But a lot of the canon trolls seem unenthusiastic about filling all their quadrants, so I suspect that in a world that *didn't* have sharp-bladed Imperial Drones coming round for genetic material on Pail Day, it wouldn't be all that odd for people to have a quadrant they just left empty, or who had a concupiscent partner they never got around to sex with.

I think sedoretu would work fairly well for asexual people of all slants; I sometimes think the problem in our society is not the emphasis on pairing off so much as the conviction that romance is necessary for pairing off. So in a sedoretu society that didn't require romance for marriage, it would be fine! And in one that did... well, ace people would be no worse off than they are now.