ok Enthes,if you going that way, i will explain you,the empire have pikemen,just look more carefully in the paintings in the army books,you will notice that have pikemen,you have been confused because will call those imperial pikes <<half pikes>> it's the same thing,it is not spear,and not only tilea has pikes,the miniatures hold their pike with to hands(two handed weapon rule),and if you want more understanding,the shields that you have noticed upon the pikemen imperial model(i am talking about the miniatures)have no effect.if you want to use the shield in the combat face to gain more armour save,you have to use the swords to fight instead for the pike(or half pike if you like).how much simpler must be it.the empire regular unit except from the halberdiers is the pikemen(or the half pikemen)not the spearmen.i think i have explained you.