How big is Earth?

[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.