Personally, I'm not a fan of D&D-style alignment, regardless of genre, but I do try to get PCs tied in to factions, religions, national loyalties, etc., which is also an effective way to generate interesting conflict and translates well into SF or other genres where absolute morality or clashes of cosmic powers aren't necessarily a thing.
Of course, the downside of this is that it's very campaign/setting-specific. If you don't know what the Cult of Gajo-Eyia teaches, or the Denkhra people's relations with their neighbors, then "this character is a Denhkar acolyte of Gajo-Eyia" means next-to-nothing to you, while "this character is Chaotic Good" is understood clearly, at least in a broad sense, even to someone unfamiliar with the setting.