I usually camp right at the end of the pavement. Advantage is that I don't have to go through the little dip in the road right at the staging area. Disadvantage is that it can be noisy.
The wide, open area you are mentioning is the predominant camping area. I think I can get my trailer in there (42 foot toy hauler), and I've seen lots of other guys go in there to camp. Should be a great group area!