I am not sure if the Romans had money coming in after the first turn without conquering or disbanding. I really doubt that. Then again, it has been quite a while since I began my Romani campaign. Ptolemies and Seleucids, from my experience, are much easier to start out with (at least from the financial perspective). People don't play the Romani because it seems like they are the easiest faction. You really don't know how difficult/easy it will be with them before they start the campaign (although the difficulty for each faction is indicated when you're choosing a faction for the campaign, I don't find that to be entirely accurate). No. Gamers choose the Romans mostly because they like the Roman history and the Roman military.
I am one of those people. I am not hiding that fact. To hell with political correctness, Romans and Seleucids were the two superpowers during the EB time period and they mattered the most. As the Seleucids declined, the Romans took their place. When comparing other nations with these two empires, those nations seem trivial. They still mattered, but not as much. That doesn't mean that we shouldn't study the other nations, its just that we need to understand the special place the Latin people held in that time period.
I have read read more than a hundred books on the various aspects of the Roman history, culture as well as military and had not found a single civilization of their time period who had so much written about them, nor one that left us so much legacy (just look at the European languages and laws - most of them are modifications of Latin language and Roman law). It was on the foundation of Greeks and Romans that Western civilization was funded, which came to dominate the globe.
Roman Empire was the most well structured in the Ancient World, if not in the entire history of human empires. It was incredibly long lasting for its time and encompassed the most vital regions of the Antiquity. If the Romans would have controlled China, they would have controlled pretty much all of the civilized and organized world. Although India, parts of Africa and America had their own civilizations, those civilizations were not as organized (in large nations under a single government) as China or the Mediterranean.
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