I found a Vanilla plus survival server on 1.20.1 that is built around a really weird world border idea. The border starts at 500 by 500 and it grows every time someone new joins. That means the world slowly opens up and it feels like the server is unlocking itself.
It also uses Origins so you can pick from custom origin choices. The owner is still taking suggestions too so it sounds like players can help shape what gets added.
There is also a Lifesteal twist for PVP. If you kill another player they lose a heart and you gain that heart. If someone dies to the environment it does not take away hearts. The server is opening soon and joining early is supposed to give you a head start.
