A comprehensive analysis of 753 empty-nest seniors across 19 Chinese provinces identified safety features and physical design as the most critical factors determining residential suitability for aging-in-place, with these elements explaining 75.4% of overall housing compatibility. The study found accessibility modifications work primarily through psychological empowerment, accounting for 67.35% of their positive impact by fostering perceived independence rather than just physical function. This research addresses a growing demographic reality as China's urban aging accelerates, with empty-nest households becoming increasingly common. The findings challenge assumptions about technology-first approaches to senior housing, instead revealing a hierarchy where basic safety and design form the foundation, while intelligent technology and social support serve as valuable but secondary enhancements. For aging adults globally, this suggests home modifications should prioritize fall prevention, lighting, and structural safety before adding smart home features. However, this is a preprint awaiting peer review, and the findings are observational rather than experimental. The research provides valuable guidance for the millions facing decisions about aging-in-place versus assisted living, emphasizing that environmental modifications must address both physical safety and psychological autonomy to be truly effective.