I do my best not to encode the things I write with any real obvious race–which means that yeah, I suppose they end up as a sort of default, which would mean they are basically white. I think that in TF fiction, most depictions of race end up coming across as stereotypes and caricatures, especially when the story uses racial TF, and that isn’t something I feel is particularly appropriate. There’s a fine line that can be walked between diversity and representation on one hand, and caricature on the other, and I suppose that the risk of the latter is high enough that I shy away from giving characters any real racial identity at all. I could do better at this–most writers could–but I think what is really missing from the genre are authors of color writing these sorts of things, or at least, I haven’t found many authors of color writing this sort of thing. If you know of any, let me know, and I’d be happy to give them a signal boost.