Seems like some races and classes get support because they are popular, and are popular because they get support. There are a few concepts out there which are so underdeveloped that it's easy to dismiss them as bad ideas or false starts or lungfish, rightfully abandoned . . . but a couple of good articles online could be enough to make us reassess them.
That's a challenge for the online writers, really --- write some really good support for the shardmind or the seeker or the runepriest, and you might end up salvaging the entire concept.