Recent growth in the scope and complexity of web-based applications has intensified the need for evaluation tools that integrate usability, user experience (UX), and e-service quality (e-SQ) within a single lens. Although each construct is well studied, their interdependencies remain under-represented in existing frameworks. Based on a systematic review of 264 sources, the original e-SQUUX model was subjected to a qualitative review by four HCI experts, who consolidated overlapping elements and clarified terminology. The resulting framework comprises 16 categories, 101 actionable evaluation statements, an explicit construct-interaction matrix, and a step-by-step Customization and Prioritization Guide. This layered architecture allows evaluators to tailor assessments to context while preserving methodological rigor, enabling holistic benchmarking of WBAs and mobile apps. An illustrative university-registration use-case—mapping ‘Navigation’, ‘Responsiveness & Helpfulness’, ‘Helpfulness’, and ‘Security & Privacy’ to concrete interface components—reduced form-abandonment from 22% to 9%, demonstrating the model’s practical impact. By merging human-centered and service-quality perspectives, e-SQUUX offers a practitioner-ready instrument for continuous improvement across digital-service ecosystems. Future work will focus on large-scale empirical validation, for example via Partial Least Squares Structural Equation Modelling (PLS-SEM).).