So far, that feels fine. Again, look at other writers, especially those you admire, and see how they filter in the details about race, gender, and so forth. It could well be that if you go far enough into the future there will be very few meaningful distinctions, but that itself might be a valuable detail. Creating a story is both the words on the page and the images and feelings in the mind of your reader. If you know that that the reader will make assumptions about things like gender, it’s almost a “gotcha” to deliberately avoid describing the gender of a character, and then say: “hah! You shouldn’t have assumed!” when you could have carefully guided their mental imagery. If you choose not to do so, be certain you have a specific reason. Same with race and other things: people will make assumptions. Unless you have a specific reason to avoid guiding their internal imagery, you should help them.