They already do.
Not exactly. Perhaps, I wasn't clear.
I was suggesting Valen's claws be "armed" in the same way a monk uses his fists- leaving an empty weapon slot and selecting the fist icon, rather than be a separate item that is equipped.
This would, IMO, leave more room for customization and balancing of the character.
I don't know if the claws work this way already, but another possibility to modify the claws are to assign a % chance of a level-drain attack. (i.e. 20% = 20 percent of hits force a save vs. level drain) This way, Valen's level drain attack can increase gradually and each level will give the PC a little more to look forward to.
This method also addresses the question of whether Valen's claws should be "dual-weilded". Like the monks fists (and feet) the claws would be considered a composite of her unarmed attack instead of a weapon that is held in either hand.
Hope that makes more sense