While LLMs have absorbed unprecedented computational investment in 2025, our interactions remain trapped in the text box—a sequential, linear dialogue that mirrors decades-old chat paradigms. To break free from these constraints, I worked alongside Decathlon's AI Innovation & Trust Team, deploying human-centred design methodologies and creative coding to prototype radical new interaction models. These interfaces transform overwhelming product catalogs into navigable, intuitive experiences that feel more like discovery than search. To validate these new paradigms, I conducted controlled comparative studies between non-linear LLM interfaces and traditional chat interfaces, collecting both behavioural metrics and nuanced qualitative insights. The data reveals critical tensions: between human reliance on spatial memory and the need to express ideas in natural language; between chat as an intuitive affordance and its misalignment with underlying AI functionality; between unclear system boundaries and usability demands for clear interaction limits. Building on these findings, the project culminates in a design framework with detailed guidelines for the post-conversational era of human-AI interaction.