While Extended Reality (XR) autism research, ranging from Augmented to Virtual Reality, focuses on socio-emotional abilities and autistic children requiring low support, common interventions address the entire spectrum and focus on other abilities, including perceptual abilities. Based on these observations, this paper first addresses common practitioners' interventions, and then suggests XR use cases and guidelines to better support them. To do so, 34 interviews were conducted with stakeholders, mainly including practitioners, and then analyzed. Emerging XR use cases were compared with the findings from two former systematic literature reviews, and emerging design guidelines were compared with the findings from a literature survey that we conducted. Findings suggest that collaborative XR sensory-based and mediation approaches could benefit the entire spectrum.