I guess not many people think the game is particularly imbalanced or don't care...
I have been thinking recently (very unusual for me) about one change that might actually really help balance - adding the armour piercing attribute to javelin attacks (skirmishers, peltasts etc.)... This would mean that the javelin throwers (I'll just call them skirmishers) are actually effective against heavy infantry unlike archers.
I think that this would greatly improve battles, in that if a player goes mass heavy infantry, the skirmishers would cause a fair number of casualties (before they use up their javelins - they don't have many, which should keep everything balanced). This should soften up the infantry for a attack by the remaining forces. So a player should be forced to get archers/slingers etc. to counter the skirmishers....... in theory...
The same principle holds for cavalry, but of course skirmishers can be easily run down, so need support.
Adding this attribute to the javelin cavalry aswell may well be effective against heavy cavalry, and as javelin cavalry tends to be fast, heavy cavalry won't by itself be effective against it.

But what are people's opinions, I've seen this suggested before, but never any real comment. Do people disagree or think this is just a given. As it is a very small change, it may be possible to bully CA into making it....... we can but hope.