So while I was going down to the CoS I remembered that we have toilets that nobody ever uses because they don't really have a purpose other than RP reasons. This got me thinking, what if we could use these toilets as a means to transport people. Just like what we did with the buckets I plan on giving these toilets a use for guilds.
So the idea is to make the toilets transport a guild member to the guild vault. The guild vault could be selected from one out of all the members a guild has. So in my case, since I have a really good vault, a high ranking official in my guild can choose to have my vault as the main guild vault that members will get sent to when they go into the toilet.
When they leave the vault they end up back in Gringott's, so in a way it could be used as a shortcut to get back to Diagon alley. Perhaps later on we could have some sort of vault with toilets that would dispense people in the CoS.
there's a vault with teleportation already
Edit: I'd like to emphasis something, there's no such a thing as a guild vault. There's a SKYSTONE vault, shared by his members. The game slightly supports the concept but it doesn't officially embrace it and it isn't going to. As far as I am concerned, the guild HQ is the clan HQ that you win when you're the most famed guild.
If you want a teleport to vault function, buy up teleport crystals charged with "vault", they exist.