Laurell's already established that the triumverate doesn't work as well as it could. Jean-Claude hasn't given them the fourth mark, they don't have nearly the kind of power they could if it weren't for Anita and Richard's hang-ups.
For the first time since I started reading the books, I wonder if it's a good thing. The council are already wary of them, Marmee Noir is far too interested in Anita for Anita's good... if they were as powerful as they supposedly could be, there would be a lot more threats coming from every and any master around, and the council. Maybe they're subconsciously holding themselves back because they don't want that attention. If Anita or Jean-Claude or whoever can make someone's heart desire manifest, maybe they just all don't want the attention that would surface if they reached their potential.
And we all know perfectly well that Richard wants to be as normal as possible, so.