It would be good to set a specific theme. For example, school, hospital, spaceship, arcade, etc... Or it might be fine to reference a specific building or floor. (In the case of sidewalk blocks, tactile paving for the visually impaired, crosswalks, or asphalt road patterns, etc.)
Please understand that I don't have an extremely high level of understanding about PBR, so I apologize that I couldn't provide better opinions.