Why do spear units have such high attack?

[Titus Marcellus Scato]

I modded my game to remove 4 points from all spear units. Works great.

[Paltmull]

Also, non-spear units often have a much higher lethality than spear units.

[Rahl]

IIRC a team member wrote that in earlier releases of EB all spear units had the "Spear" attribute which gave them +4 attack against cavalry and -4 attack against infantry. Though the spear attribute adds a lot of pushing power and the result was unrealistic behavior of the units. So they changed that to "light_spear" which gives +4 defence against cavalry and -4 defence against infantry. The stats where not significantly changed since that so the attack of spear units is still very high. Sadly that makes spear units slightly overpowered.
I changed a lot of unit stats to balance things out but I didn't touch the attack after thinking about it. Just reducing the attack would make spear units to weak but giving defence instead also seems to be not perfect especially because that would make many spear units weaker against cavalry (and the bonus against mounted units can't be used because that effects all weapons of a unit, so archer-spearmen would slaughter cavalry with their bow, swordsmen with spears would kill cavalry to fast with their swords...)

Even without changing the stats EB has a good balance, not perfect but good enough to ignore the higher attack stats of spearmen.