we are all learning from the same folks ahead of us it seems :)
I agree with other comments though the devil is in the details of how to actually setup these "golden signals" so that they are useful and not just drown everyone in packet level non-sense.
One thing of note in the graph is the tracking of response size. This would be very useful for 200 responses with "Error" in the text. Because then the response size would drop drastically below a normal successful response payload size.
In addition to Latency, Error Rates, Throughput and Saturation , folks like Brendan Gregg @ Netflix have recommended tracking capacity.
Right now we maintain few select percentiles from the latency distribution over 1 min time-period. We plan to maintain latency histograms which will allow you to look at latency distribution on arbitrary time intervals.