Not the worst movie I've ever seen but certainly not the best.
No idea what the character of Lee Harker was ultimately about. It's never clear what her deal is.
Longlegs could have worked better if they'd had someone unknown/less distinct than Nicolas Cage. His absolute Cagey-ness was just very distracting from any genuine fear one night feel about the character.
Predictable, in many ways. Lots of things not really explained or followed up.
Lots of hype, didn't really live up to it.