This study introduces bidirectional stepwise-based algorithms designed to optimize loudspeaker array configurations for Multizone Sound Field Reproduction systems. An initial arrangement selection method based on loudspeaker magnitude enhances the optimization process. These algorithms were validated using the Acoustic Contrast Control and Pressure Matching methods across free-field conditions and a comprehensive Room Impulse Response database including various room conditions. Comparative experiments against traditional unidirectional iterative strategies demonstrate that the proposed algorithms significantly outperform existing methods in terms of efficiency and effectiveness, especially in configurations with fewer loudspeakers. For example, in a small meeting room with 16 loudspeakers, the stepwise-based approaches achieved higher acoustic contrast and required substantially fewer iterations than conventional methods. Specifically, optimization efficiency improvements were about 55.2% and 77.8% in Acoustic Contrast Control and 36.7% and 68.6% in Pressure Matching, compared to conventional iteratively adding or removing approaches.