The devs of Ara have released their 21st dev diary, in which they talk about the goverment systems in Ara.
As in the civ games, you start with a basic type of government, and you unlock new types in the research tree. While the government types have positive modifiers, it’s unclear from the video if they also have negative modifiers, but the devs said they had a look at the historical impact of the governments.
The leaders have some shared traits, similar to Civ3 and Civ4, and some of them will have synergies with some forms. The other details are a bit more vague, but have a look at the video yourself. And come discuss it with us here.