One of the challenges when developing a visualisation tool, especially at the start of a research project, is to amalgamate numer- ous requirements and various possibilities and decide what to create. With software development, it is too easy to incorporate all ideas, but quickly the tool becomes unusable, with feature overload. We reflect on designing and building the ColloCaid collocation visualisation editor, especially our conceptual focus on simplicity. We were inspired by Hemingway’s iceberg theory of deliberate omission, to help frame the visualisation challenge and achieve clarity and focused design. The ColloCaid tool enables people to discover collocations, to help people improve vocabulary and fluency as they write. It was developed by a multidisciplinary team of applied linguists, lexicographers, human-computer interaction and visualisation experts. We promote focused design and problem solving, in visualisation, highlight concepts, including parti, design essence, and simplification. We provide a collection of insights that hold potential to evolve into a structured set of design guidelines, offering valuable direction to researchers.