Well, to me, the extra 1 pound that the ntb MBP weighs over the rMB is negligable a (for about the same price) you get and extra port, larger/brighter screen, stronger CPU, better speakers, better camera. To me, the only reason to buy the rMP is if one values portability over everything else. I have the late 2016 ntb MBP and my wife has the 2016 rMB. I have tried hers and the trade off is simply not worth it to me.
Aside: My wife (with the rMB) is only 5 feet tall and 115 lbs and has to take her laptop every where with her as she is a language teacher. So, for her, a person who needs less capability, doesnt use the camea or speakers much, needs little power and is very small in stature....the small form was the guiding principle in her selection. She is very happy with it.