When constructing my user stories I generally will identify on what type of persona the user story perspective is from (pretty standard Scrum). It would be nice if I could build a list of Persona's that are relevant to my project (or refine for an Epic?) so I can flesh out their details/traits/perspective of them (could be mostly free text description, a name, title and graphic), and then tie the available persona(s) to my user stories. This way when developers are completing the work related to the story they can have a solid understanding of the individual trying to do this task. To assist with project planning, it could be useful to narrow down the work that is going to be performed by focusing on a specific set of user persona's (and thus related tasks), and gradually re-introduce the other persona's in later releases of the product. This could be delivered in a method similar to the Agile "Columns"