Yes. All of their powers are sort of related to each other, like enhancements. And they're also extensions of themselves. For instance: Avery, drug user, kind of a social outcast, very socially awkward. It makes sense for her power to be invisibility because that's the way she likes it. Her second ability, glamoring (which is like appearance shape shifting), is an extension of invisibility because she can be anything she needs to be.
I actually like the sound of this, a lot! I'm always up for interesting, new series based on magic/witches, because television seems to be too caught up with vampires and spies, they forgot about this genre all together. Though, it seems like this idea is slowly, but surely, returning.
Clairvoyant (kick ass title, by the way) has a very solid plot. It seems to set up a new universe, its characters and the conflict they have found themselves in, which makes me eager to discover their journey toward getting out of it xD Overall, you've got a great idea, and this is definitely the type of series I would follow closely so, keep working on it.