well yeah you can do player made events. i was thinking about doing this but it's probably not worth it because a lot of good artists are gone, unless you're willing to spend a lot
You don't need express permission from the staff to create an event. The Event's board is free to use for anyone, providing you follow the rules outlined in the stickies.
If you want the event to happen in some form of official capacity - you can always apply for ES sponsorship. Check this out: