I made a crew list the other day that rocked in a small tournament at my local LGS (and won) but I'm not sure if it was completely legal. Basically I used Ama No Zako to lead an 20 point Arcanists crew. She is a henchman and has the mercenary trait but I recall from somewhere that only models from their proper faction can lead crews. I was mostly wanting someone to confirm that this was or was not a legal crew.