Leveling Alt. idea

So this is just something I thought of while waiting for the un inevetable demise that is FFXIV never come back up.

What if SE allowed us to lv. an alt while in a queue or waiting for that new error? What I mean is if we try to log into our main character and it says please wait until there is room, or puts us in a queue, what if there was a way for SE to let us stay in the queue, but load up an alt. and play on that, And than have a message pop up that says "you are now able to log into this server".

Kinda like how playstation home works if anyone has done that, where you are able to be in one area while waiting for another area to download, you can still do anything you want, and than when your new area gets d/l'd a message just pops up saying this new area is ready, do you want to go there now or stay here?