Usernames aren't difficult, it's just a technical limitation that overloads the server whenever we try to do it.
Emblems just have a lot of steps. We used a third party script to make emblems possible and it wasn't coded the best, and I just haven't taken the time to make it easier. Basically you have to upload the emblem images separately using FTP and then go into the admin panel and fill out a form with the paths and everything. It isn't that it's difficult, there are just more steps than there should be.