Physical therapy has lagged behind other fields in healthcare in the adoption and integration of emerging technologies and new media tools in clinical practice. However, the Covid-19 pandemic, the rise of telehealth and virtual medicine, and increased accessibility to virtual reality (VR) headsets like the Meta Quest have created an opportunity to revitalize the field and kickstart progressive thinking for rehabilitation. Games like Supernatural and businesses such as XRHealth are actively combining VR technology with traditional rehabilitation protocols in gamified designs that are both fun for users to engage with, and more or less supported by rehabilitation sciences. Adopting participatory design as its method, this study gives a platform to domain experts in the field of physical therapy to envision the future of physical therapy and supply ideas and suggestions for VR rehabilitation applications. We first examine problems in the physical therapy field, including both clinician burnout and barriers of access for patients, then engage physical therapists in discussions about these issues and potential ways VR technology can provide solutions. Some of the design elements proposed by the therapists are integrated into a design prototype named Simulacra, which serves as a possible blueprint for future game design and development. The ultimate aim here is to spark more progressive conversation about emerging technologies in the field of rehabilitation, and make contributions to the growing list of effective design principles for physical therapy in VR. Results indicate a strong curiosity towards VR and a desire from physical therapists to see more technology integrated into their work and improve the healthcare they are able to provide. The interdisciplinary line of questioning used in this study was welcomed with open arms by the domain experts, and future work can take the conclusions here and apply them in functional prototypes to be tested with both physicians and patients.