This is how we decide the difference between the event types:
Official events are planned by the server's staff members. User events are events planned by the server's Trusted members or below.
If a user event were to become an official event, it would have to be reviewed (in whole) by the server staff, since they are treated as major server events. As much as we'd like to have a ton of official events, we can only allow a certain number of events to become 'official,' based strictly on the resources that can be considered and due to the fact that official events involve as many people as possible to attend.
I would agree with having it as a child sub-forum of Events, but I just want to remind everyone what the difference is between the two types of events and why we only allow a certain number of 'official' events.
As always, all events should be planned out ahead of time, but official events require more time to allow for more planning and even any revisions if the event takes a different route or if there are differences in available resources.