Well, for the time being they don't really need any "specialty models", as it were.  Site #144 specializes in some of the nastiest (and technically illegal) experiments known to man, and their products often never actually see the light of day for that very reason.  It's not the kind of place that would make something like Nine, who is actually a valuable asset to the rebels.  They keep a healthy stock of things like Satyrs and other basic GenMods, but most of the really deadly stuff is completely mindless or in so much pain that they could never be permanently controlled.