How big is Earth?

[PvK]

Generally I think of Terra as a medium planet. In the real universe, when you exceed your planetary capacity to support native life, it doesn't help and the natural consequences tend to wipe your species out until something wiser evolves.

[Fyron]

Luckily we've never seen anything close to an exceeded planetary capacity in the real universe.

In Adamant mod, at least, your homeworld(s) start out filled to the brim and seething with unhappiness, providing a great impetus to move out to the stars for a better life.

[capnq]

Perhaps that's why homeworlds never have Optimal conditions: they were optimal back when your species evolved, but now population pressure has degraded the environment.