I'd be very interested to see WWE at HHN, especially with this concept. The Firefly Funhouse and the Fiend were fantastic angles, and there's just so much potential and the brand synergy here actually works. People may dismiss this because it's wrestling, but like Fallon's Tonightmares, I would actually suspect this may be far more successful than the premise would imply.
If they focus exclusively on the Wyatts without WWE forcing them to do a bunch of unnecessary cameos, this is likely be much more horror driven than most people would suspect. Honestly, a Wyatt family kills the WWE universe or simply tortures John Cena a la WrestleMania would would be fire.