I'm sorry but I think that someone complaining that their flanking "is useless" is much more of a pedantic issue of someone being annoyed that braindead playstyles arent rewarded... flanking will always have a tangible benefit, even if its just to have more of the enemy being killed because of more contact with your units.
Right now, this is the synopsis of this game:
the fact that fighting the ai is basically unrewarding, easy and a repetitive cakewalk is much more evident by the inumerable submods which attempt to increase game difficulty in all kinds of ways rather than submods that do the contrary.
all it takes is 1 cavalry, and no matter how elite their units are: they are going down.
in the battle above, 1 cavalry unit routed multiple seleucid hoplites and chalkaspides phalanxes (which routed with 248 out of 256 men). How absurdly exploitable morale is in this made a battle that should've been a loss an extremely easy victory, the enemy had like double my size during the start of the battle, and also they had elite units... which meant nothing. (btw, fyi the cavalry unit had a kill count of 800).
If you think this is acceptable I'm going to start looking for submods that remove some of the most cheesy aspects of morale mechanics, or try to do it myself.