The growing integration of renewable energy in modern electric utility system has made load frequency control (LFC) increasingly important. This study explores various power system models, refinement techniques, and control methods to strengthen the efficiency and resilience of LFC. It focuses on Proportional Integral Derivative (PID)-based LFC in microgrids, examining seven optimization techniques across four cost functions, with random step load perturbations to assess response reliability. Preliminary results show that the new Cohort Intelligent Optimization (CIO) algorithm outperforms other methods in achieving optimal results while maintaining efficient computational costs. The CIO-ITAE (Integral Time Absolute Error) optimized LFC also exhibits improved resilience in addressing microgrid challenges. This review helps researchers bridge gaps in current advancements, applications, and future developments of microgrids in LFC.