“Requirements visualization” to me means the ability to look at the project and determine if you need to document simple workflows or create high end simulations, or something in between. I think ideas are born once we put them to paper. Paper is where ideas are recorded, copied, shared, and accessed by other people (sharing). Designing the diagrams representing the user paths feels natural on paper.
Instead of process diagrams and flowcharts, why not create a clickable website instead? I jump straight to what I know: HTML, CSS, and JavaScript. In a couple minutes I have a basic page layout and basic navigation to click through the scenarios, before we leave the conversation.
The reason I needed a clickable, “*medium-end” prototype for my health care app project is because the client needed to learn what they were asking for was not what they actually wanted. Paper diagrams with user paths would not have worked here because the client could not relate to paper, but could relate to clicking.
