The concept of human-centeredness exists in the fields of software ergonomics and artificial intelligence. In this work, we propose how key principles from both disciplines can be applied together in a unified software design process. While the research community for legal artificial intelligence is well-aware of common requirements, such as explainability and privacy, work on Human-Centered Design focusing on creating and evaluating the user experience is rare. We contribute a blueprint for future legal system design optimized for user experience and common requirements of legal artificial intelligence applications.