This paper outlines a requirements-analysis process that unites task models, scenarios, and critical parameters to exploit and generate reusable knowledge at the requirements phase. Through the deployment of a critical-parameter-based approach to task modeling, the process yields the establishment of an integrative and formalized model issued from scenarios that can be used for requirements characterization. Furthermore, not only can this entity serve as interface to a knowledge repository relying on a critical-parameter-based taxonomy to support reuse but its characterization in terms of critical parameters also allows the model to constitute a broader reuse solution. We discuss our vision for a user-centric and reuse-centric approach to requirements analysis, present previous efforts implicated with this line of work, and state the revisions brought to extend the reuse potential and effectiveness of a previous iteration of a requirements tool implementing such process. Finally, the paper describes the sequence and nature of the activities involved with the conduct of our proposed requirements-analysis technique, concluding by previewing ongoing work in the field that will explore the feasibility for designers to use our approach.