hehe.
why should one survive 3 arrows if he dies after 3 melee hits as well anyway. 
You rly think that an arrow and a 2h/polearm should be the same dmg?

When you are attacking someone as a melee class, you are normally in a big danger. As a melee you can be hit by every class in the game, if you are dealing damage to someone (in most cases).
As an archer you are at a distance, and not in a huge danger. As an archer you might get hit by other ranged, and maybe the cav, if u are standing in a poor spot.
So basicly the risk/reward would be very unbalanced.