In regard to your point on ergonomics, try this site - https://cycle-ergo.com/ it will allow you to check leg and body angle, plus pillion ergos, and is adjustable for bar raisers etc. I found it invaluable on my search.
Thank you Steve. This is a very good resource. Currently they dont have the latest generation of the 1250rt and plugging in the latest that they have (2014) shows that the knee angle of the rt is the same as the ST. I hope newer generations have improved this. As mentioned by others, the GS series have much more leg room. I will have to throw a leg over them at a dealer soon. Thanks again.