Universal Seed
Written by Dennis Cleaver, and his demons
I hope it's not a common suggestion, I didn't check.
What do you mean?
Everyone generates the world with the same seed, but spawns in a different place.
The world is huge, why don't we use all of it?
Shared world doesn't need to mean Multiplayer.
How?
Keep the world gen options, mods and seeds.
Make one seed the default, and add a checkbox saying "Random Spawn", more on that later,
Why?
Culture, Fair(er) game-play, Realism, and Ease of Access.
Culture - communities grow around Points of Interest, and trade of locations begins.
Fair Game-play - About to quit because you can't find some resource? How about you ask on the net, find the nearest location and travel there. It will take you a long time, but the resource is guaranteed, and you have not cheated at all.
Realism - Our world works like that.
Ease of Access - Newbies can just disable "Random Spawn", and there will always be a tutorial to help them, unless the update changes the world - everything is guaranteed.
The Technicalities, or Why It's Possible, and why it's gonna be hard.
"Random Spawn" mechanic checks current time, the Unix Timestamp is just a number that can be fed to an Algorithm™ to determine the players spawn location. Just make sure the algorithm keeps the player in approximately the same climate. This sprays player all over the world, with natural hot-zones created by a lot of people joining at once.
Now, there's an issue.
The world needs to be both small, and large. Small enough to travel, large enough to explore. The current 1 Million limit is far too large for anyone to take in, traveling to any landmark would take weeks of constant playing.
We can either make the world smaller, or make modes of transportation that speed it up so a mere human can take it. Something that still keeps the exploration actually challenging, so no absolute teleportation.
Afterword.
The cultural significance is of upmost importance to me, traveling to places the community deems important would feel like climbing the mount Everest. Discovering and exploration would revisit the times of colonization. We can let go of logic every other sandbox game was built upon, and build one world that binds the community even further.
Thank You for your attention, and hope for a warm reception.