Mixed reality (MR) is considered an effective medium for enriching museums with digital content, enhancing the visiting experience with interactive and playful elements and contextualizing the exhibits and the physical space. Especially in the case of intangible heritage, where human practices and traditions cannot be easily expressed by inanimate objects alone, targeted MR installations may provide an additional source of communication and dissemination with active user involvement. However, the wide variety of approaches, paradigms and technologies that have been developed so far create a large design space with little feedback on the impact of each design choice on visitor experience and learning effectiveness. This chapter reflects on the design, implementation, and user evaluation of three Mixed-Reality installations in respective museums in the Aegean region in Greece, highlighting intangible cultural heritage, and more specifically industrial and craftsmanship heritage. The installations utilize methods from interaction design following iterative evaluation cycles, from concept creation to final system development, both in the laboratory and the museums’ settings, and inform on the suitability of the adopted processes. The three MR design approaches range in terms of technological configuration and affordances, interaction metaphors and user’s perspective, users’ collaboration, gamification, education, and entertainment. Based on the results of the field studies and the intermediate user evaluation cycles, we present how user experience can align with the conceptual design inspired by specific nuances of the presented intangible cultural heritage, focusing on local craftsmanship, industrial heritage, and the working culture of the people in these places. In addition, the chapter provides design recommendations for other researchers, practitioners, and professionals working in similar museum and heritage contexts.