I have reworked both the vanilla and your map.
My largest changes have been getting rid of the later years huge pop jumps,
making Asia minor a tad more populous, removing a few people from Mesopotamia, Redistributing the population in Asia minor towards the west and the coasts. Um, i removed a number of people from the Carthaginian provinces, especially Libya/Cyrene. Added some Pop to Egypt.
For example, Italy had about 4m people south of the Po in 474, Carthage as a total probably didn't have 2m in total including Southern Spain in 474.
Syria had about 2m+ people in 474, but Palestine only had maybe 400,000.
At this point lower Mesopotamia only had about 500,000 people total while Assyria et al had about 750,000 people. The entire population of coastal Tripolis and Cyrene was only 300,000 or so with another 100,000 nomads wandering the desert to the south.
On the other hand, Western Persia up through Azerbaijan (today) there were 3m+ people which the game does not really reflect.
Greece, Macedonia, Epirus, had about 2.5m or a hair less. Epirus had no where near the population or culture this game gives it. Aetolia should have fewer people.
Asia minor had 5m or so people, with 2m+ in Bithnia, Pegamum, Lydia, Caria.
Tunisia had a total pop of about 1m+ at this time. 700,000 in Morocco, 1.5m or so in todays Algeria.
One thing this game does wrong is it follows the wacked out capitalist model that everything always increases. That is just not how the world works. In this period population was holding steady or in some cases falling with the only real rise coming in Asia Minor and Italy, and Italy's increase was a mix of more land under cultivation in the north and the huge influx of slaves. But even this only brought the population of Italy south of the Po up to 5m, and north of the Po to 2m.
Mike