I've been monitoring your thread as your set looks intriguing (alas my addiction to NCAA 14 has kept me from playing M15 for a while). I can tell you from experience that if you want the CPU QB to throw errant passes and not be Robo-QB-like (as you pointed out on your OP), you have to drop it down to at least 4 before you start seeing a significant difference. Don't worry, they'll still be effective at that range (I actually think 2 or 3 is best).