Actually I agree, 90 or even 80 deg E is far enough to include Bactria without the entire Indian subcontinent. Even at that a Mauryan (Indian), Bactrian and Xiong-nu civilization could be added to flesh out the scenario in the east. Actually, since longitudinal distances are shorter at higher latitudes, on a flat projection the eastern border might 'bend' from about 80 deg E in the south to 90 deg E in the north. And similarly in the west. But, these dimensions would be sound and permit encompassing a great area of historical interest. A sub-saharan African culture, Ethiopia (Axum), and Arabia in the south, with exploration around the Arabian peninsula. A Gaelic, Scandinavian and Slavic culture in the north, with navigation in the Baltic. This would cover the areas that many of these civilizations had contact with in ancient times. There also needs to be a few more realistic features like mountains and oases in the mid-Sahara. Maybe the Etruscans would fit on the Italian riviera, and Israel can be squeezed in to the Middle East. But I know it is pretty ambitious for game designers to expand this to 34 civilizations - the larger scale map focused on the Mediterranean and Middle east is still a good compromise.