Unlike Syrian or Seljuk armies the Fatamids get a decent quantity of solid foot. Against contemporary opponents the Zanj swordsmen probably should be Bd. List-selections for these battles is interesting. Rough-terrain troops are being minimised or dropped entirely. Basically all armies are built around a core of either mounted troops or solid infantry.
Nobody wants to fight in rough terrain so the rough-terrain guys become spectators and redundant.
Crusaders could do with less missile troops and more spearmen.