Sorry for not answering this in a more timely manner, darling, I wanted to give it some thought first!
My personal favorite is utterly genderless angels. As creatures of spirit, there’s no reason for them to have an sort of innate idea of sex, and since gender is a social construct built around the idea of sex, there’s no reason for them to have that either. When I write angels, I tend to write them utterly bemused by the concept, irritated when people call them “he” or “she” because that’s as accurate as referring to someone as “that purple.” They’re a different species, alien and magnificent and strange, and the way they think about themselves and their identities is going to be just as alien. One of the easiest ways to show this is the concept of gender and sex, since it figures so heavily in the way we think about ourselves.
You also can do really fun things with given names and the idea that angelic language is drastically different than human language. I wrote a short story once where a group of humans couldn’t decide whether their guardian angel (whose full name was unpronounceable by human tongues) was to be called “Jo” or “Joe.” The angel literally couldn’t fathom why this was important to them—mostly because they were in the midst of the apocalypse, and had more pressing issues to resolve, but also because xe thought it was a stupid debate. And I love that so much, still.
But this all goes hand-in-hand with my idea of angels as non-human shaped things—wavelengths or spirits or even whatever these are. Even if they’re inhabiting bodies belonging to humans, they’re still something else, something other, and the something other can be genderless. But if they’ve got bodies, bodies they consider theirs, that’s a different story.