Due to time constraints, I never got to troubleshoot further the problem I originally posted about. I left my Hitron in Gateway mode despite having a Cisco router downstream of it. It worked (~600/20Mbps) even though I knew it is bad idea to have two devices doing routing in my network.
Upon seeing @edgewater's post above, I revisited the issue. I checked my Cisco router's QoS setting. It was OFF. (Check box empty.) On a lark, I decided to turn QoS ON. With my Hitron in bridge mode, after I turned QoS ON, I went from 80/20Mbps to 90/10Mbps. Hmmmm. Something is going on here. :-)
Then, I turned QoS OFF and I got:
So, apparently, on my Cisco RV130W, you have to toggle QoS ON and OFF in order to actually turn off QoS. YMMV.
Thanks everyone for helping me solve this problem.