I have been looking at the Later Zhou as a possible Chinese army to build, and as they transformed into the Song in 960 CE with Zhao Kuangyin's coup I have inevitably drfited into the Northern Song period as well.
This has made me wonder about the classification of the Northern Song infantry. I read that their formations were 1 rank of troops with a mix of spears, pole arms, etc, 3 ranks of crossbowmen and a final rank of archers. This feels more like classification in the Five Dynasties list (half SSp + Xbow, half Xbow) than in the Northern Song (all Pole Arm + Xbow).