In my Scream 4 i would make it about Re-makes...
Like in Scream 2 where there is a supposedly copycat killing people who have similar names,stuff like that but not exactly the same.... except in the fourth previous survivors from "Scream" who weren't as "main characters" would return,The two girls in the toilet saying sids mother was a very *friendly* person,the kids from the party,(including the ones who himbrey suspended) Hank loomis,Sids dad,obviously Sid,dewey and gale, and of course Sheriff burke... the murders can take place on the anniversary of the massacre in woodsboro in the first film, with a new killer making his/her own re-make how they like it,not always aimed at sidney as the main target but with intentions on taking out previous survivors of the whole thing previously... Maybe have a main character or 2 new ones getting offed at the start just like steve and casey!! the more i type this,the more my head keeps getting ideas... But, definitely a return to Woodsboro