I much rather get stunned than lose half of my hp from a spam arrow, however, you cant nerf both things (stun or dmg), archers need to be efficient some how, so go ahead and choose one, would you rather die from a skip the fun archer in siege, or would you rather get stunned. And ofc the stun is realistic, have you ever got shot by an arrow? oh it stuns you alright, unless you are an orc from lord of the rings.
And one more thing, nerfing the dmg would make most noob archers give up and only the truthful ones stay, those who fight with tactics and team work (hence the "fun").