I like it.  I ran a Call of Cthulhu campaign once, using a similar premise.  Loads of fun.

Anyway, to clarify, are we expected to create OC of different genres and then mash 'em up for funzies, or is this a multi-verse style RP that intends to draw from pre-established works?  Or is "screw it, both of 'em" on your mind?