As enterprises increasingly rely on the Salesforce ecosystem, Lightning Web Components (LWC) have emerged as a powerful solution for building dynamic and responsive user interfaces. However, their adoption at scale raises challenges related to performance, design standardization, code maintainability, and long-term sustainability. This paper investigates architectural design patterns and performance benchmarks relevant to LWC development within large-scale enterprise environments. Emphasis is placed on aligning LWC practices with the principles of sustainable software development, which advocate for resource efficiency, modularization, low technical debt, and long-term maintainability. Through empirical analysis and practical case studies, this research evaluates the effectiveness of established LWC patterns—such as container-presenter, service-based architecture, and state management strategies—and measures their impact on rendering speed, memory usage, and maintainability indices. The paper further proposes a sustainability-aware LWC development framework tailored for enterprise use, providing guidelines to ensure scalability, performance, and environmental responsibility in digital product engineering.