bmmccarthy
This is called a "thematic" roadmap or an "outcomes" roadmap. It is well described in this article: https://www.prodpad.com/blog/the-birth-of-the-modern-roadmap...
In my experience, feature requests are someone's best guess as to the solution to a problem, but often without the problem statement. When you ask about what problem the request is meant to solve, you come to understand your customers -- even better, you realize there is a much shorter list of important problems than of feature requests.
Focus on solving those core problems and most of the feature requests will melt away.
A roadmap is a tool for communicating long-term direction and priorities. By making clear what the ultimate destination is, a roadmap helps you keep steady on the those priorities when doing your sprint planning. When sales says "we want this feature to close this deal," if it's something already on the roadmap, great. If it really doesn't fit with the long-term vision, you have a basis for saying no.
I wrote a book on this topic, Product Roadmaps Relaunched, Setting Direction While Embracing Uncertainty, for O'Reilly a couple of years back that goes into more detail: https://www.amazon.com/Product-Roadmaps-Relaunched-Direction...