I'll get the major cons out of the way first. This movie suffers from the usual problem Hollywood film always seem to have -- no money to afford electricity. Most of the movie is shot entirely in the dark, so goodness knows what happened in those scenes. Also, one or two key bits of dialogue that explain what's really happening are totally lost to mumbling.
However, overall, this film really did improve on second watching. Once you know what the story is, you spot all sorts of little bits of detail that make the whole thing make sense. But more than this, my empathy with Grace, the protagonist and victim, grew exponentially during this second watch. She comes over as an almost wholly sympathetic character. Little things like the carefully wrapped presents she brings and hides make her rather loveable. Her love for her dog and what he represents to her is very moving. She's a very damaged person, but unfortunately for her, she gets entangled with other very damaged people and hell hath no wrath like grieving children.
There's only one jump scare in this movie, but it's a good one. The rest of the film is a more slow psychological horror about the power of grief and early childhood trauma. And human fragility.
I highly recommend this to anyone who likes their horror thought-provoking and real rather than shock-horror jump scares. This clearly borrows from Hereditary: almost shamelessly copies much of the atmostphere of that film with the dark house, the dolls' house, the cult, the dolls, the camera work inside the dolls' house distorting our perceptions.
Pretty good movie with strong performances all round.