This might seem as counter intuitive, as there are folks that hijack ideas for a living, But hey, F*IT; lets hear your craziest plots you can concoct. We'll be the judge of them.
I'm down for a good laugh.
Muppet Harry Potter, where the only human character in the entire series is Luna Lovegood. Everyone always talks about how odd Luna is, but never actually addresses the fact that she’s human. Also make a point of tongue-in-cheek noting how stereotypically awful many of the characters are.
But also, the thing should never be made because JKR would just funnel all of the money straight to some neonazi group.