As Gears pointed out, with the previous SCPF epic tale Wanderlust claimed by Fishmonger's temper tantrum, it falls to the current membership to create a new epic. An epic, ideally, written as a collaboration of many authors and incorporating the input of the SCP community as a whole. There's no time like the present, so how about we start with some brainstorming of plot ideas/elements?
My thoughts:
A story like this has the potential to heavily glorify the characters involved. For that reason, I'd suggest creating one or more new researcher/agent/administrator/janitor/D-Class characters as the lead protagonist(s), whose ownership belongs to the SCP community as a whole rather than to just one contributor. All of the existing Foundation luminaries should of course play significant roles, and get their time in the sun, but leave the final spotlight on a character not associated with any one author, even if they're an unsung hero in-story.
Rather than revolving largely around one person's SCPs, the new story (or stories) should focus on either some novel threat, or on a mix of several authors' SCPs. It should also include many or all of the most iconic and beloved SCPs, at least in cameos. It goes without saying that any appearance by SCP-447 shouldn't involve contact with dead bodies. Seriously, the explicit nature of a story would go against everything that makes that article great if you actually described what happens.
tl;dr: This should be a community project, and thus should draw on characters and SCPs from many contributors.