Some MMO's that had really popular and very big communities, often found a way to let everyone access an area, and not overload things at the same time. LOTRO for example, their Landroval server is the unofficial RP one, and thus had a very sizable community when I used to play. But traversing this one city of men, was a nightmare because of the crowds.

So the suggestion is to take a page from their book, and layer the server. Like set a hard number of what the area should be able to safely hold, and force the server to create an instance duplicate layer of that area to start dumping people into. Friends who want to be in the same layer, and group up and select an option to move to their friends layer. It might help with the gold saucer. Oh and bring back the afk-auto-boot. I've already started seeing people who have gone afk to goto bed in gold saucer. They would rather not fight the crowds, by preventing others from getting into the gold saucer. That sort of selfishness shouldn't be rewarded.