A question rises in my mind "how to define an instrument?"  It reminds me that some artists usually make unique sounds out of everyday objects. For example, the Vegetable Orchestra performs on instruments made of fresh vegetables, Bruno Zamborlin transform the whole bicycle into a music interface for interaction, Trashbeatz even created the beat out of trash, etc. These inspire me "wow" might come from an "everyday" surprise.

To make abstract concept more intuitive, I proposed to consolidate all ideas together and set the concept of a rainy garden with a beautiful greenhouse and many seed beds in the open space for the sake of aesthetic and discovery user experience.  Players can imagine themselves as a gardener to create their own music by planting vegetables, managing the trash and observing growth changes.