Technically Rome has different classes of citizenship. You could be a citizen but not part of the voting class of citizen. I think it's important for people to be considered citizens if they are born into the society with ancestors from the society etc... It's just the privilege to vote must be earned. Not even sons of the most prominent leaders should be given instant voting status unless they meet the requirements.

Must be naturally born in the country - This ensures (for the most part, barring minor exceptions) only people who've experienced the culture and values growing up vote. This is important for these people to align with the overall culture and values of the society. This prevents immigrants with competing culture/values from coming over and disrupting things for the people who call this country their home. This will overall create a more unified political system with the interests of the domestic people at heart. It may also create a disincentive for immigration and ensure the people who immigrate do so because they truly want to live in the country and respect the culture because they have no say in its politics.

4 years voluntary military service - This ensures some perspective regarding risking one's life for the safety of the country and understanding military discipline. It's important for developing wisdom and perspective in a prospective voter. No ivory towers who've only grown up in the academic system can vote. They need at least some sort of experience and this is a good one. Not everyone wants to put their life at risk nor do they actually respect the military enough to join it, even for the right to vote. This ensures those people don't get to dictate what goes on in the country at a political level.

Must have biological children - This ensures some skin in the game. People will vote for more long-term position over short-term because they have children they care for and will want to leave them a society. I think too for declarations of war etc... when it's potentially your kids going rather than a single person with nothing to lose, you make better judgements because you better understand what is at stake.

Must be male - Men and women are different. Society has a better outcome when men are primarily in charge of State affairs, not women. Take a look how single women vote and it's pretty telling. A woman's impact on State affairs should be in how they raise their children. In that regard they still vote through the influence they have on the next generation. Let the men actually vote. I do not believe men and women are equal in terms of how they vote. Men are more likely to vote for freedom while women are more likely to vote fro security. This has a huge impact on the direction of a society and not in the good way. Giving women the right to vote has increased the size of government immensely.

Must have net positive tax contributions and a minimum level of land wealth. This ensures the people voting are people who've proven their ability (or ancestors at least) in contributing to the wealth of the society. None of these people are going to vote for welfare systems that drag a country down unless that is truly what they want to do because these people know what it's like to work to earn a living and not rely on the State for what they have. When you let anyone of any wealth vote, such as people who have nothing, they can vote to take more from others without contributing anything themselves and this is not desirable at all. For the most part, ensuring these things will ensure the people voting have a minimum level of competence which is desirable.