Recent advancements in ultra-precision machining center have significantly enhanced the capability to produce high-quality aluminium alloy components with improved accuracy, superior surface finish, and extended tool life. The growing demand for precision-manufactured aluminium parts in industries such as aerospace, automotive, biomedical devices, and electronics has increased the need for optimized machining strategies. This study examines the influence of various machining parameters on key performance measures, including surface integrity, dimensional accuracy, and tool wear, during the machining of aluminium alloys. A Definitive Screening Design (DSD) experimental methodology is employed to efficiently evaluate multiple process variables and their interactions while minimizing the number of experimental trials. This approach facilitates the identification of the most significant parameters affecting machining performance, enabling data-driven optimization of the process. This study investigates the micro-milling performance of uncoated WC tools with 7% cobalt binder, unlike conventional 11% cobalt tools, as a suitable choice for machining softer aluminium alloys. The work uniquely integrates experimental trials with ANOVA-based statistical analysis to capture the influence of spindle speed, feed rate, and depth of cut on cutting forces and surface roughness. The findings provide process-level insights and evidence based guidelines for optimizing micro-milling of AA6063-T6. The study highlights that spindle speed is the most critical parameter, contributing nearly half of the performance variations, with optimized settings achieving superior surface finish of 0.0384 µm and reduced cutting forces, thereby extending tool life and ensuring stable, high-quality micro-milling of AA6063-T6 (ASTM).