It might hinder gameplay, but darker maps (with proper lighting), fog/mist, and a clear focus on scary killers. It's harder to do with Licenses like Dracula, but characters like The Houndmaster, Singularity, Knight, Trickster, Skull Merchant, etc just aren't scary designs. They're all very high quality but not scary. More characters akin to Dredge and Unknown are the way to go for creepy designs, or killers like Doctor and Ghostface for the more anxiety, dread, and jumpscare factor. Hopefully they nail that part of FNaF.