Why are you pinging an intermediary router, which is likely going to be unresponsive to ICMP?
How about pinging Google for 50 iterations; and just post the summary, because that has all the information that you need to show:
I don't think your signals show a problem, but I will defer to any DOCSIS experts, if they disagree.
Your trace doesn't look bad, but it is a single point in time. A PingPlot might show something.
PingPlot to Google over time.
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum