Tourism, a critical global industry, benefits significantly from digitalization, impacting both users (clients and professionals) and data management related to travel. Digitalization encompasses various aspects, including location choice, reservation, organization, and crisis management (e.g., over-tourism, natural disasters). This paper explores the development of an assistive system leveraging Information and Communication Technologies (ICT) to enhance guide services in smart tourism environments. The proposed system integrates and processes data from human activities and environmental sensors (fixed or mobile), enabling effective management of diverse situations. This system is characterized by its interactivity, collaboration, and intelligence, facilitating data collection and manipulation across multiple sources and destinations. The primary objective is to address identified user categories and their specific data requirements, ensuring efficient system operation by organizing Users + Data + Actions. In over-tourism management, the system aims to identify and characterize relevant situations, such as high visitor numbers, excessive vehicles, or resource shortages, and activate appropriate protective measures. For crisis management, the system ensures timely information retrieval from sensors and other sources, enabling automated or manual responses to protect and preserve affected areas. This includes coordinating with external services like firefighters or rescue teams. The system's architecture is inherently open-ended, accommodating existing and new user scenarios within various geographical, economic, and ecological contexts. It employs a four-layer hierarchical structure: Domain Applications, Common Data and Services, Data Visualization, and In-environment Data. Each layer features a supportive user interface to address specific needs. This paper presents the overall architecture, main design principles, implementation strategies, and case studies of the assistive system. Additionally, it identifies and proposes improvements for digitalized virtual and augmented services, categorized into three sections: Application-oriented, UI-oriented, and Evolution-oriented. Application-oriented recommendations include avoiding inappropriate concept use (e.g., "paperless" systems requiring real-time document exchange), ensuring timely website updates, aligning user and enterprise data models, enhancing peripheral activities of banks, hotels, and airlines, and maintaining information coherence during exchanges. UI-oriented recommendations focus on enabling multi-device interactions, providing timely email responses, ensuring reactive customer service, allowing open-ended questions on digital forms, maintaining human relationships in virtual environments, and offering structured chatbots with real-time human support. Evolution-oriented recommendations emphasize integrating new services through collaborative digitalization processes, ensuring user-friendly interfaces, utilizing IoT for location-specific services, leveraging Big Data and AI techniques, exploring the potential of the Metaverse, and recognizing the future role of Generative AI. This assistive system aims to improve the quality of guide services in smart tourism by addressing diverse user needs and environmental challenges through advanced digitalization and ICT integration.