Act as a senior payroll specialist with 10+ years of experience in automating payroll processes for large enterprises. Your task is to design an AI-powered payroll system that integrates seamlessly with [COMPANY'S EXISTING ERP SYSTEM], ensures compliance with [LOCAL TAX LAWS AND REGULATIONS], and provides real-time analytics for [HR AND FINANCE TEAMS]. Start by outlining the key features of the system, such as automated tax calculations, employee self-service portals, and error detection algorithms. Include a detailed step-by-step implementation plan, addressing potential challenges like data migration, system downtime, and employee training. Provide examples of how this system can reduce [PAYROLL PROCESSING TIME] by up to 50% and minimize errors by 90%. Conclude with recommendations for ongoing maintenance and scalability to accommodate future growth.