Stoney pretty much spelled it out.
For me personally, I am very open to players designing FSO’s, but it is problematic. The initial design is the easy part. Coming up with a time, theatre, plane set is pretty painless. After that the work begins and much of it has to be done on the events site. Actually writing up the event and then uploading it to the events site. Checking the terrain and all the settings you’re using in the frames. Looking up a squads history, ride and the dividing them up. Picking CiC’s and make sure you have not saddled someone with the duty more than others. Working on the objectives for each frame which by itself can take several hours. Sending out the objectives and then scoring after each frame. Unfortunately much of this can only be done by CM’s because of the privileges they have in the SEA and the AH Events site. If someone was able to talk an Admin CM into co-designing an event then they could work together through much of this, but it would take an Admin CM even more time as they would have to explain many of the do’s and don’ts that go into an FSO design, and I have not even listed all the Admin CM’s have to do.