Sorry to be late, but here are a few of my picks:
Beetlejuice: I never thought this could ever come to the event. Then GhostBusters brought in the biggest crowds HHN has ever seen. This one has been speculated by everyone, and completely makes sense for the more family-friendly vibe Horror Nights is trying to promote. We know and love the character at the park, and the sinking ship that was HMH is sure as all not using him (even if I want them too). There's just enough to create a maze, and the Tim Burtonites will flock to it without thought. I'm really considering this.
Hill House: Disclaimer that I haven't watched the show. It sounds fantastic, but is a big investment for the little amount of time I have. Netflix's connection to Horror Nights has been pretty great, and without real reason to do ST3, they can use Hill House to bring in younger crowds that don't have a connection to the older, cult franchises. The show seems to have a dark tone that would be great to replicate in a house, and Netflix will probably demand a soundstage, which is a win for all of us.
Mexican Original: As soon as I went through Holidays, I knew this had a chance. It seems they purposely didn't add Mexican holidays, since they would almost be mandatory in such a mixing pot city. LA's latino dem loved La LLorona, and they have the safety of having increased cultural knowledge when compared to Spirits and Demons. They can reuse quite a bit from El Cucuy and La Llorona, and maybe even use the skull throne figures from pandora for an Aztec/mesoamerican section.
Creepypasta original/Slenderman/Russian Sleep/ Channel Zero: The inclusion of a Momo type character in Spirits and Demons shows that horror nights is trying to appeal to younger horror trends. Mixed with the mention of Channel zero in the survey, their strengthened connection with sony (zombieland, GB), and new Russian Sleep Experiment movie (is that still happening?), I think an original take on creepypasta, or an IP house from a creepypasta based movie, could be very likely. NGL, I don't want this to happen since I know every vlogger (cough cough JPLAND21 cough) will make a "REAL JEFF THE KILLER:wow:" video, flooding all maze POVS with 9 year old kids asking if the blood is real.
INVISIBLE
MAN AND DRACULA: Their posters were featured in the vault this year, so out of any of the Universal Monsters, their inclusion would make the most sense. Plus, they can piggyback off the Invisible Man movie they're releasing with Blumhouse next year. I think we all know Universal Monsters are coming back, just a case of who.
VERY WISHFUL THINKING Alice Cooper's Brutal Planet: The albums turning twenty next year, and that era was probably the most to be aligned with haunted house. Great industrial aesthetics, but I know it isn't happening.
EDIT: I'd diea very happy man if they did an Abott and Costello house, as impracitcal as it seems.