What you are discussing is a funnel for a customer feedback loop to iterate on your product.
The good news is that lots of lean startup advice exists to help and guide you solve this problem.
For an in-depth view of The Lean Startup and the measurements and metrics you should track to improve your product you can start with the Eric Reis book, Lean Startup ...
It's like continuous quality improvement. It is about continuous improvement of the customer experience. Or the person is responsible to manage / develop / improve/ increase the customer experience, e.g. over the project lifecycle.