This paper presents an optimized economic evaluation model for intensive drilling in unconventional oil and gas development, based on the “well factory” concept. The model integrates cost components—including pre-drilling, drilling operations, drilling materials, and drilling fluid treatment—with synergy factors that capture the benefits of centralized operations. These synergy factors reflect cost savings arising from reduced land acquisition, optimized rig sharing, and enhanced reuse of drilling fluids. Furthermore, a decision timeliness component is incorporated into the objective function, ensuring that the model can dynamically balance cost minimization with rapid decision making—a critical requirement in fast-paced energy projects. The model is rigorously developed by building on conventional cost equations and is validated using field data from the Shengli Oilfield Yan 227 block. The results demonstrate significant reductions in pre-drilling and drilling operation costs under the “well factory” mode compared to conventional single-well approaches. Additionally, an optimal platform configuration is identified, highlighting the economic benefits of integrating centralized infrastructure and shared resources in large-scale drilling operations. This comprehensive framework provides a robust decision-support tool for enhancing economic efficiency and operational effectiveness in the development of unconventional resources.