With many thanks for your suggestions, I've added a "Face" slot to the Horror Mini. I also added a "Randomize All" button because, come on, random zombies = fun.
I cheated and just copied/pasted the Warrior faces into the app since I'm so short on time. I could probably do the same with the FacialHair one, but that'll complicate things a bit for the female version. Do-able though. The Warrior Hair items don't seem to fit all that well, but if you want it I can see what I can do. Ditto for the Backplane.