I'd love a family friendly Universal Studios Halloween event. Ride overlays for Minion Mayhem and Simpsons and all the facades, all the characters in Halloween costumes, trick or treating and trails around the park, include Hogsmeade and Hogwarts (which would be perfect since the Wizarding World loves Halloween but Rowling is not a fan of HHN as a whole), different shows (Bring Beetlejuice back!), and heck, maybe a kid friendly spooky maze with tame scares?
Not as tame as Disneyland but still fun! I'd so be down for something like this, especially with the direction USH is going. There's lots of possibilities! Grinchmas is a huge, make a similar Halloween event! Imagine Universal Plaza all decked out as a Graveyard with a show and maybe a large icon of some kind (instead of a Grinchmas tree), etc