At the very least, adding a proper 'third eye' glamour would be of benefit at this point in time. It's already possible for players to design a decent looking Pureblood Garlean if they so wish - and quite a few role-players choose to do just that.

In terms of playable options, a clear distinction is made between Imperial Garleans and regular Garleans - and even then, there's examples of working with the former out of necessity/mutual benefit.