Only two AAR:s for EB have achieved a legendary status. The first is The Wasteland, the second is The World According to the Koinon.
I'm eagerly waiting on Quirinus next AAR (rumor has it it's about the Sabaeans).
The Pahlava however aren't a pure steppe faction. Not in the current build anyhow.
But neither the Saka or the Sauromatae have a decent AAR in their name. They have a unique government system, face great challenges and have a basically invincible army of HA at their disposal.
The Scythian invasion devastated most of the civilized parts of the world during ancient times.
It would be nice to read an AAR on another steppe people bringing terror and destruction to all those "civilized" nations in the game.