I'm designing a sci-fi videogame.

But I've many doubts about the hierarchical structure.

On a ship "the captain" is the highest authority, directs, coordinates and controls all activities, responsible for everything and is the representative of the crew.

On an interstellar journey, using a generational ship (journey of many generations) and considering that:

• The initial crew could be 60,000 people.
• The crew becomes a reflection of a society in a closed ecosystem.

In this scenario the figure of the captain is lost since we would speak of an authoritarian government, a dictatorship.

What system of government do you think should be used in a generational type ship? Parliamentary, federal republic, representative democracy, athenian democracy (updated) ...

What powers would exist?