I agree with the OP as well, even though your example of 80k archers vs. 3k towers and some odd defenses is not a good one.
However, range is king in this game and because of the archer tech, archers have a huge bonus in their attack. There prob needs to be a tech where infantry units move faster in battle to counter that. The attack and defense tech is nice, but it won't help a single troop that fails to even make it to the archers.
Archers are broken. Allow me to demonstrate:
http://battle4.evony.com/default.htm...6b13e34e71.xml
Note in that single attack, the attacker got over 400k honor.