Let's answer the titular question: Hub Worlds are an important part of any medium, especially games. They are, in many cases, the connecting glue that binds the world and story together. However, some are better than others, so with this threat, we'll clearly see which hub stands above the rest!
Here's who submitted:
@Daikaiju
@Baudshaw
@SabreCat @Torzelbaum
@Johnny Unusual
@Issun @Violentvixen
@Kirin @Patrick
@Beta Metroid
@Falselogic
@JBear
@Aurelia @WildcatJF
@RT-55J @Lokii @Dr. Nerd @spines
I know it's disorganized... if only we had a convenient location to put them all!
Before we get to the actual Top 50, we'll do some honorable mentions first.
These hub worlds were #1 for a single person, but no one else.
@Daikaiju put Paris from Sly Cooper 2. It's strange putting a real city here, even though it's very different in the game and much more charming. Even still, the real Paris belongs nowhere near this list.
Next, @Falselogic had Cyclops from Subnautica. This is a pretty clean and advanced submarine, although I heavily doubt you'll be able to spend the whole game cooped up inside it.
Then, @Issun put Blackwell Academy from Life is Strange. These musty-looking hallways are the perfect place to learn more about the school and its students.
Finally, I put Aviary Village from Sky COTL. You can see how my profile picture originated from it. The mysterious Hopeful Steward is in charge of this place. Notice the doomed mountain of Eden in the background.
Here's who submitted:
@Daikaiju
@Baudshaw
@SabreCat @Torzelbaum
@Johnny Unusual
@Issun @Violentvixen
@Kirin @Patrick
@Beta Metroid
@Falselogic
@JBear
@Aurelia @WildcatJF
@RT-55J @Lokii @Dr. Nerd @spines
I know it's disorganized... if only we had a convenient location to put them all!
Before we get to the actual Top 50, we'll do some honorable mentions first.
These hub worlds were #1 for a single person, but no one else.
@Daikaiju put Paris from Sly Cooper 2. It's strange putting a real city here, even though it's very different in the game and much more charming. Even still, the real Paris belongs nowhere near this list.

Next, @Falselogic had Cyclops from Subnautica. This is a pretty clean and advanced submarine, although I heavily doubt you'll be able to spend the whole game cooped up inside it.

Then, @Issun put Blackwell Academy from Life is Strange. These musty-looking hallways are the perfect place to learn more about the school and its students.

Finally, I put Aviary Village from Sky COTL. You can see how my profile picture originated from it. The mysterious Hopeful Steward is in charge of this place. Notice the doomed mountain of Eden in the background.
