Allow me to answer this from the perspective of one of her own:
Quick, what's the first thing you see when you spot a character? Yeah, you're not going to spot anything you asked about before looking at what they're wearing. Also doesn't help either that miqo'te is still the most played race on practically any server and au'ra females use pretty much the exact same frame as the miqo'te female model.
Another thing that doesn't help either is that there are only so many hairstyles, facial features and so on and only a handful of ones that people prefer, so there's bound some duplicates in terms of style, further amplified by the sheer number of cat girls and the au'ra that almost look like them.
The last thing that would provide this perspective is that usually in MMORPGs with multiple race options, players are more inclined to see differences among characters of the same race like everything you listed. An miqo'te player is more inclined to spot finer differences among other miqo'te, whereas everyone else just sees catgirl #8172 and normally wouldn't spot those finer differences unless they actually took time to focus on those differences.