I have towed a small trailer on my past three bikes. The hitches I installed on the first two bikes were home-built, and I just tapped into the existing wiring. On the last bike (Goldwing) after much surfing and comparisons, I purchased a hitch and plug-and-play wiring harness from RIVCO. Much nicer and easier to install.
Now with a new 2018 Venture in the stable, I need to once again install a new hitch. While there are a couple of different hitches out there, I REALLY liked the RIVCO design and attention to detail. They don't have one available, but after contacting them I found that they do have one on the drawing board.
According to RIVCO, a new hitch AND wiring harness may be available in November. I have no idea whether it will just tie into the sub-frame (as all the other hitches do) or tie into the main-frame, but however it attaches, I'm sure it will be sturdy.
I am especially excited about the wiring harness. If it's like the harness I got for my 'wing, it should plug into existing connectors without compromising the existing wiring. They also have a trailer light relay/isolation module available. I believe this will be important since all of the lighting on the Venture is LED - the existing wiring probably won't have the capacity to provide power to additional lights - especially incandescent lights.
As I hear more, I'll pass it on.