That still makes them quite weak against missiles. Seems odd to see chariots falling from 1 or 2 arrows, when even the infantry can withstand more. They should be prottected against arrows more than the basic cavalry. In the reallity, the arrows/javelins can't do anything against the cart, and also against the armoured crew. Only, if they hit horses, there would be some effect. Or maybe, the chariots should start runing amok, after missile fire, representing that the crew is dead, and the chariot is out of control.

But I doubt that two arrows can kill two crew members and horses + cmash the cart