Only select few civs should have access to chariot archer upgrade such as Egypt and maybe Babylonians and Assyrians since they have no access to Heavy Horse Archers.
85 HP, 7 range, 5 attack, no armor and has conversion resistance like other chariots. That was my idea how strong that unit could be.
New unit and unit upgrades ideas for Return of Rome - Age of Empires II: DE / II - Discussion - Age of Empires Forum Here is my post about new unit upgrade ideas that should be in RoR.