A mechanic that makes no sense, as I have already said. But hey, if you want to put modern concepts, I want Dinosaurs. Shooting lazers. And giant lizards. It'd be called Dinosaurs vs Giant Lizard along with fantasy greece
Too bad the athenian democracy wasn't nothing like what it is said Really, it wasn't even a democracy when they didn't care about who voted or not, it was an oligarchy- A democratic one, if you want, but I'm from that school that thinks that Greece is so full of myth, BS and, overall, is overrated, that thinks that it wasn't that good and that we should take another look on it.
What's wrong with that gameplay mechanic? It works just fine in Europa Universalis IV and it could be easily used to portray for example Greek leagues. I would like to have more serious and elaborate answer about the cons of that mechanic than attempt to turn this whole discussion to joke about dinosaurs and lasers.
And BTW I'm familiar with Ancient Greek political systems and their development during the centuries, so I don't know what you hope to achieve by telling me that Athenian political system had occasional oligarchic tendencies, besides underlining the fact that you don't like Greece.