I played a game against three difficult computer opponents on the Area map, a large map with abundant resources, and stopped at the Castle age.
I set up double layered walls and castles filled with archers before leaving the game running overnight.
I chose Byzantines as my civilization for higher HP buildings.
To minimize my unit losses, I used the castles to advance and disrupt their trade lines, slowing down their attacks.
Then, I pushed with the castles towards each of their bases, eventually defeating them.
This may not be everyone’s preferred style of gameplay, but I personally enjoyed it.