There is no real/not enough combat balance between units
I have been playing the game for a while but only really noticed this problem now.
So what reasons are there for not just making your whole army archers?
As far as I can tell, they can do just as much damage as melee units and sometimes more, plus they can strike at all times and don't have to spend any time walking towards the enemy. Also, because archers (and correct me if I am wrong) can be given army just like any other unit they aren't actually any worse at melee combat then any other unit. They just stand still and take the same amount of damage, and then attack once it is their turn.
A great example is a battle I just had with an enemy army that was 60% archers. I attacked it with 2 heres and about 5 melee units. In terms of size, our armies were similar. I battled the enemy's melee troops and won but still took some considerable amount of damage from enemy archer fire. Then after killing the melee troops I sent my heroes and troops after the archers. "Hahaha, now the enemy is screwed since archers can't possibly stand a chance against melee troops in close combat. I mean that's just common sense, right?" I thought to myself. But then once my already damaged troops got to the archers and attacked I discovered to my horror that my melee troops weren't actually any more effective against archers then they were against other melee units. Being unable to defeat the archers with their high hitpoints and defense, the enemy archers butchered the rest of my army.
I am sorry, but if what I suspect is true (and please correct me if this is just some nonsense and I am missing something) then this utterly ruins the game balance. What is even the point of building melee troops if archers aren't actually any worse in toe-to-toe combat then melee AND can attack units anywhere on the map at any time?
I know that melee units have some special abilities that archers don't, but those don't compare to the ability to strike from anywhere like archers can.
EDIT:
Now that I think about it, the problem isn't just with archers. As far as I can tell there doesn't actually appear to be any difference between units other then the weapons and special abilities they use. Archers aren't weak against melee units, cavalry isn't weak against spearmen, etc.
In my opinion this makes the game unbalanced. Archers should not be able to go toe-to-toe with melee units and expect to win, just like cavalry should not be able to go toe-toe with spearmen and expect to win. This game really needs to give different kinds of units bonuses as well as penalties against certain unit types.
For example, units armed with spears should get a 50% melee bonus against mounted units, while archers should suffer a 75% defense penalty when attacked in melee combat. It would make combat much more logical.
Thoughts?