Briefly, I'd like to summarize a topic we had in the german development thread to maybe hear some non german speaker's ideas.
In Pie's Ancient Europe, the tech tree, much according to late ancient history, comes to an end. That means, nothing left to research, no more buildings to built, no paratroopers posing, or mechandroids from the toy shelf. While you're winning, you need something fun to do, that, at the same time, adds to historical accuracy and isn't too complicated.
So why not adopt the Corporations of Civ and assign Sid's Sushi Co., Aluminum Inc., et cetera, the role of one of the mystery cults of late antiquity, such as Mithras, Isis or Manichaeism. Instead of the executives, cult missionaries will be sent out who work exactly the same way expanding the new cult, providing boni to a city, maximizing the income of a commercial city or letting a rival bleed financially.
Unlike religions, that are passed by parents unto their children as a public duty of all individuals, these mystery cults are adopted by adults, who aren't satisfied with their official religions, and that are practiced in the obscure. Different religions affect diplo and cause war, mystery cults don't.
Pie's first draft was:
-) Horus cult (Egyptians, with Egypt. Gods): +1

, +1

, +1

-) Totenkult (Egyptians, 2500 BC): +2

-) Schamanism* (Huns, 2500 BC): +1

, +1

-) Matriarchalism (everybody, 2000 BC): +2

-) Demeter cult (Greeks, 1300 BC): +2

-) Mithras cult (Persians, mit Bündnisse): +1

, +1

, +1

-) Heroic cult (Greeks, 700 BC): +1

und +[no smilie for this, what does it mean again?] ?
-) Cosmogonisms (everybody, with Philosophy): +2

-) Hellenism (Greeks, 300 BC): +1

, +1
*With the huns gone in the next update, adieu Schamanism.
Mine:
1. Horus Heliopolis (with Egypt. Gods, with quest* 100 AD): +3

und +1

per used ressource, consumes precious metal ressources and stone-ressources
2. Isis Heliopolis (with Egypt. Gods, with quest 100 AD): +3

und +0.75

per used ressource, consumes (land) food ressources
3. Serapis Memphis (with Hellenism, with quest 300 BC): +1.5

und +0.5

per used ressource, consumes (water-) food ressources
4. Dionysos Thebes in Greece (with Olympian Gods, 600 BC): +4

und +0.5

per used ressource, consumes wine
5. Kybele Anatolia (with Ackerbau, with quest 100 AD): +1

und +2

per used ressource, consumes mineral and stone ressources
6. Mani Seleucia on the Tigris (Perser, with quest 270 AD): +6

und -0.5

per used ressource, consumes precious metals und minerals
7. Mithras Southern Turkey (with Professional Soldiers, with quest 100 AD): +2

, +10 experience for new units in the city per used ressource, consumes iron and bronze.
I'm not getting into translating where the discussion took from there, so you get a chance to unbiased opinions. Any?
*with quest: in addition to researching the required technology and owning the necessary ressource and having the appropriate specialist (in this case, priest) to found the Corporation, you would have to settle at the particular place where the cult historically emerged, pretty much the same way as the "holy mountain quest" in Civ.