I've just ended a two week hardware hackathon I was on, and it was interesting the organisers advised us to spend half of our 7 minute judging-pitch-presentation
on the user stories - to identify for the judges we were addressing a real problem and not just doing technology for its own sake.
Afterwards I had the insight that Scratch would have made a great tool for this - for example to animate a heavy vehicle and light vehicle approaching the same intersection. And then I remember we have Phratch.
So an interesting concept would be having Phratch in the Pharo Catalog under the title "User Story Tool" - and have end-users writing simple blockly scripts to describe their domain, then as the main developers write Pharo code to fulfil these requirements, it could feed working features back the animated user stories.