The biggest problem with Scott Derrickson’s Sinister for me was that Bughuul (Bagul?) was sort of dopey, though considering that that mythical dream demon was the engine that powered the movie, that’s a pretty big hurdle to overcome.
If the trailer for Sinister 2 is any indication, it appears that director Ciarán Foy (Citadel) has tackled the issue of the inherent silliness of the character head-on. His answer is to weave a feeling, an air, of mystery around the character, often by obscuring him in shadow, and making him move by way of quick edits.
From what I can see, it works. There are moments in this trailer that make him appear genuinely creepy.
So far, so good.