Okay, you've just blown my mind. It's one of those things where you never think of it but when someone points it out it seems so obvious. So thanks!
So, on the mindcrack server, if you want to explore territory with new content you just go to an unexplored part of the map - they have a rail hub in the nether for fast travel. On the original server this wasn't possible because LC was hosting it himself and had bandwidth constraints. With beastnode we haven't yet had to limit the size of a map.
This is definitely something to consider, though at this point we have all put so much work into mega-projects scattered across different maps it will be hard to give up. On the other hand, it always makes me a bit nervous committing to a big project when I know the map could be gone in a month or two. If we do this I think we should resolve to keep the same map indefinitely - years even. When we want to explore new content, we set out for un-spawned chunks.
This doesn't mean we need to give up multiverse (though it does play hell with the nether), but maybe it's not a good idea to spawn a new world every time there is an update - we really are all scattered about, which was part of the motivation for the Skeptiville project - create a space where we could build together. If this idea picks up speed we have to decide which worlds to get rid of. NemorisCrux is the newest world, so I'm inclined to make that our homeworld (not the least of which is because I built the infrastructure for Skeptiville there). I have an unfinished mega-build on gliese581d (the mushroom tower over the borehole) that I would hate to loose, but if it helps the community I'll give it up. Some things could probably be cut n' pasted to Nemoris.
It may also make sense to get a second server for challenge maps, that way the primary build world has a dedicated server - and the nether would work right! Of course, this would eliminate the whole export/import issue entirely. Maybe when a challenge map is finished I can shoot the map over to Z so that the victory monument can be copy/pasted into the build world.
So here is my take on this:
1. Keep multiverse but pare down the number of maps.
2. Have only one core map for building and exploring which is permanent (I vote NemorisCrux)
3. Have challenge maps that are temporary, but may stay up for months after they are beaten for resource extraction to designated zones like Skeptiville.
OR
1. Get rid of multiverse
2. Dedicate the server to NemorisCrux (or some other map), which will give it a functional nether.
3. Get a second server for challenge maps (some of which have nether content that multiverse prevents us from accessing).
Doing this would also make all of the import/export restrictions much simpler to deal with (or eliminate the issue entirely). If you want to do the whole start from scratch survival thing you only need to travel out to new areas of the map and bring nothing with you.
I'm a bit attached to my older builds, but if they had all been done on one map to begin with I would have nothing to loose. Remember, the only reason we "needed" a new map back in the days of the original server was because we couldn't go beyond 1000 blocks from spawn (this was for bandwidth issues). If that map had been hosted on beastnode or elsewhere we might still be playing on it.
I would be willing to pay for and maintain the challenge server (though I will need help from Z as I don't have a clue

) Beastnode seems pretty cheap, especially considering the level of activity we see. I can't see it costing more than $10 a month, and that is only if we get lots of skepti-peeps interested in the challenge maps.
Thoughts?