Like it was already reported, the main issue is that Arrows do full damage, whatever the distance travelled. This has a huge impact on gameplay and makes things really weird (like in Total war games, and basically most of games).
This is why you can have "God Tier" mounted units which combine Speed + Damage + Long range + Precisions (+Armors, etc...) without any real drawbacks.
In reality, mounted units would charge to close range, Fire arrows, then go back before contact in order to make some damage (especially for armored units). They are then vulnerable themsleves to arrows/bolts and could be intercepted by others cavalry (even heavy cavalry).
The solution would be to have arrows/bolts make more damage at close range, and lower as the distance increase (especially versus armored units).