I would like to start a Survival map for myself and I'm planning to play on it for a long time. But I have a couple of questions, before starting it.
Is there a possible way, to pre-generate the map? (With a program, not by flying in creative.) I mean, I would like to generate my map in a 3000 block radius, so if a new version of Minecraft come out with a different terrain generation, then there would be a straight line, a border for new lands.
My other question: Can I somehow re-activate the Killer Bunny spawning in Survival? I know it has been removed, but it would be fun, the encounter with it someday. If I can't in vanilla is there mod for it? I tried to search for it, but i didn't find anything.
I'm not sure if there is a way to pregenerate your world, but if you want to make sure, noone goes outside of those 3000 blocks, you could setup a World Border. That will also make it possible for you to generate new chunks outside of that area and thus generate the new terrain.
You could setup a commandblock contraption that randomly spawns (a) killerbunny(s).
(If you need help with that, let me know, I'll provide a setup and some commands)