I also particularly liked your nominal chart. It’s a great example of what Edward Tufte calls “small multiples” and how proper design can allow us to easily understand and comprehend charts that are also data rich. That is, much of what it takes to communicate is good message design, not overly simplifying the message.

Also, good point about using the measure of the queue as a signal to take action. That can happen far faster than using cycle time as the signal because of the time lag. (Classic Queuing Theory–great stuff.)