This paper develops a proposal for topology-aware packet classification and adaptive local-core selection in SpiNNaker. A dispatch-class mechanism refines standard routing table entries by restricting inter-chip forwarding directions and reducing local processor-mask fan-out. A reproducible virtual-mode benchmark compares the proposal against a static-routing baseline across 960 trials per ablation. The combined refinement reduced a synthetic energy proxy by 18.28% on average, with processor-mask refinement identified as the dominant contributor. Results are software-defined proxies, not hardware-measured energy claims.