TPC, after reading this thread and thinking a little, I`m pondering on giving ap attribute to all melee weapons. Reasoning:
1. At high armour ratings, which are quite common in EB ap weapons are MUCH more effective than normal ones. If your opponent has 10 armour (for example humble thureophoroi) an ap soldier has a +5 attack compared to a regular one. That`s too much of an advantage IMHO. And remember, that there a lot of units, who have more than 10 armour...
2. It seems reasonable to me, that an ancient suit of armour would be more effective vs missiles (hence no ap for missiles save those, who already have it) than melee weapons. Even a heavily armoured soldier may be knocked on the ground and have his throat cut by a dagger.
3. Armoured soldiers would be much more vulnerable from their backs, where their defense skill does not work - which is a good thing IMHO. Keeping formation would be important for everyone.


This "solution" does have an obvius downsides. First of all, we will no longer have units who are more effective at killing armoured foes - less tactical diversity. Next, all weapons, which already had an ap attribute would need to be rebalanced (by increasing their lethality or attack)