I wonder how you are going to represent the fact that what plagued the Persian Empire were the incessant revolts by mainly the Egyptians and the Babylonians. IMHO persian culture should be weak, while Egyptian and Babylonian culture should be very strong. This would mean that large complements of troops would be needed to prevent flipping. (In reality the troops were stationed outside the cities.) Since there are precariously little architectural and litterary remains of the Archemenid Empire that would perhaps mean that the Persian Monarchial government should incorporate the new elements of the Fascist government, which inhibits cultural growth. The satrapies, which is a very good gameplay idea should produce little or no culture.
This is how I see your starting position. You start as Cyrus (leader unit) with a complement of Elite Archers. (according to Russian excavations palatital bodyguards were archers) The Median empire is in anarchy. The city you start in, Persepolis, have just revolted from the empire, and you see the opportunity to grasp the weakened Median empire quickly. Persepolis is located in desert. Luckily you are agricultural, in addition to being industrial and militaristic, so desert can be irrigated. Even better is it that your civilization have mastered the art of cattleherding, moving the cattle back and forth between the hilly uplands and the schorched lowlands according to the temperature of the seasons. In short cattle abounds around your prosperous city. Amazingly your people have through hard work dug deep tunnels, also know as 'qanats', (edit: spelling) into the the hills. Under these hills the groundwater table is raised, and the water can be led out unto the hills. Summa summarum the land, even hills, can be irrigated without acces to surface water.
Well, these were some ideas.
BTW. I have an idea for a new wonder specific to this Scenario. The Commagene Nemrut. The site is placed at the top of Mount Nemrut in the Turkish province of Adiyaman. Essentially it is the grave of King Antiochus, who supposedly is buried under the Tumulus. A Tumulus is a mountain of stones. What is interesting that the deities which are placed the foot of the Tumulus facing East and West represent a syncrestic mix between Persian and Greek culture and religion. So in some symbolic way it represents the end of Greek/Persian rivalry. (The kings of Commagene were no friends of the Romans). I propose that this wonder could represent an ancient version of the UN wonder.
Post Scriptum.
I am unhappy that Arabs are not going to be in the game. When Cambyses invaded Egypt he specifically had to ask the Arabs for a right of passage((According to Herodotus)
Have you considered naming the Athenian city and their allies, simply the Ionians?