Right now, our server's players really enjoy making huge tunnel systems, but there's always a problem; the space down there is verrrrrrrrrrrrrry limited. Only room for 5 levels of stuff, and that's when it's pretty cramped. If the amount of vertical space was increased to make the map more cube shaped that would be great. Maybe even an ability of the server host to increase the map's size in-game.
I second this. I was going to post a new thread and decided to just tack on to yours in support. I have been hitting the cloud-ceiling in my level far too early when I'm building my little towers. Might not be as noticeable if you could alter the sea-level, but I'd still love to have a far larger height in the environments than what there is now.