This issue feels less about Viera and more about Hrothgar imo. I think SE can easily add Viera to the list when releasing new hairstyles and just as easy port existing mog station hair to them.
However it would look bad to give it to Viera while Hrothgar don't get anything since they were added together. Safe to assume that anything Hrothgar gets, Viera will too and vice versa. Which means that even if there's something that could easily be applied to Viera, if it's not just as easily applied to Hrothgar, it won't happen.