The CRAFFT (Cosmic Ray Air Fluorescence Fresnel lens Telescope) project is developing a simple fluorescence detector for the next generation of ultra-high energy cosmic ray observation, which is similar to the concept of the Global Cosmic Ray Observatory for example. Beyond the Telescope Array or Pierre Auger Observatory, it is inevitable to expand the scale of the experiment. The key concept of the CRAFFT detector consists of mass composition sensitivity and low-cost production and operation. The CRAFFT detector is a simple structure fluorescence detector with a Fresnel lens and has fewer photomultiplier tubes than conventional fluorescence detectors. We have already successfully detected air showers with the prototype of the CRAFFT detector and optimized it for improved shower reconstruction and a larger field of view per detector. We are also planning to conduct test observations with the optimized detector to confirm the observation concept. In this contribution, we will report the current status of our project, the details of the optimized detector configuration, and future plans and preparations to confirm our observation concept.