Yep, the peasant women you can sometimes hire? Train them and they kickass. There is one more merit to archers, and that is that so far the most OP unit I found in Gekokujo is an archer.
One merit archers have over gunners is the attack speed, since a hit staggers the enemy the archers would be the ideal unit close behind your infantry to support them through and ensure not only more damage but the enemy not being able to hit back as much. Gunners reload slower but deal a lot of damage per hit and are fairly accurate, in longer battles or ones dragged down as you both settle for range combat, archers don't do much damage and run out of ammo being obsolete, gunners can last to the end, if well managed with hold fire when enemy is not near, even for 200+ battles. Most of all what you didn't put into account is the most important piece of information: Gunner wins, you just have to place them right.
