Oh, a few things we might want to consider for when we do update the servers. Slimes and witches may spawn in swamps - any swamps. Also, minecarts and mobs will be able to go through portals to the Nether. This might mean that you occasionally get unwelcome visitors into your homes on Frontier. Also, mob farms will no longer be as effective but you can xp in more ways.
The Admin team will deliberate things like whether we need to extend the world borders yet and whether the division needs any rules for new things like command blocks (which only the admin team will be able to spawn), other than "don't be stupid".