I'm just going to make an observation here. Its my own observation, and it may be that none of the other admins support it. But here it is.
I see some ideas here that, personally, I like. I'm really glad to see the creativity. We need more of that. Keep the ideas coming, please.
Also, I've been an admin for awhile and working with the whole plot thing for awhile now. What I've seen, in general, get the most response on PA is not always the easiest to design. But--it seems to work better if there is an overall site plot theme that, while it encourages and invites the entire membership, it does not hinge on one or two key players. Nor does it hinge on mass threads for the plot to work. Neither have, by tradition, been successful her when they are used as the foundations for moving a plot along. In fact, those things seem to stagnate a plot here quickly. Mass threads, key characters, etc., can be used as fun or as additional elements, but they tend to not work so well as main site plot elements.
Also, when a site plot also has enough development to it to encourage members to be able to revolve their own personal plotting around it, it tends to get more response. Some members here prefer site plotting and some prefer personal plotting. And then there are some that enjoy both. That means that sometimes a PA site plot can become a bit tricky to forumulate.
When we can manage to design those plots that contain the above mentioned elements, activity on the site stays up and it seems to keep people happy. Don't know if those thoughts help, but its just what I've noticed seems to work or not work so well here.
I probably just confused you all more.