Why bring Archers as Bretonnia?

I know they're cheap, but it seems to me Bretonnia mostly wants to fix the enemy in place with cheap line infantry and then use the overwhelming cavalry force to pick off the enemy backline, and cycle-charge the rear of the anvil. From this perspective, a unit of archers seems like a wasted *slot*. With a maximum of 20 units, why wouldn't I prefer a unit of Mounted Yeomen? An extra unit of Yeomen, in place of archers, can better harass the enemy backline and keep routing enemies running away by chasing them.

Archers may be useful against flying opponents, but then they have to land at some point anyway and it seems the archers would get get in trouble when attacked directly, so the Yeoman seem preferable for the slot.

Against large units Archers are obviously cheaper than Knights of the Realm, but again it seems preferable to have Yeoman to herd enemy routing/backline units and allow Knights of the realm to focus on the larger enemies, rather than having Archers + KotR or Archers + other cavalry.

In domination I can see archers as a cheap way to get bodies on a point, but there surely men-at-arms would be better because they can hold longer against attacks and if bodies on the point is really the goal, a peasant mob would be more value than archers.

The only reason to bring archers I can see is to specifically counter regeneration with fire arrows, in which case it might be worth bringing a couple to prevent regeneration. A fairly niche requirement, I'd generally prefer yeomen.

With 20 units, is there any reason to grab a unit of Archers over Yeomen cavalry except for specifically fighting regen?

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Usually I would bring

1 Lord, 1 Priestess, 6-8 line infantry (spears/polearms), 2-4 Foot Squires (sword and board in the early game) to target enemy anti-large infantry, and the remainder of cavalry distributed between anti infantry and anti large.