But AR works wonders against super annoying army compositions like chariots, horse archers, berzerkers (not that the AI gets to make them) and Egyptians in general.
Wussy The Middle East is where you're supposed to post all those veteran Principes you accumulated fighting in Greece to cover your Archer Auxillia while they toast all those chariots! But....

....I suppose you are right. When there's no player to oppose the Big E, facing down endless stacks of gold does get boring.

The best city to do that with is Carthage since it has insane farmland bonuses.
In the vast majority of my games, it is usually Carthage (in the hands of the Scipii) that bring about the Marian reforms.