Spoilers...
The cop and ex wife are pointless. They literally add nothing to the plot. At first, it seems like they are there to create drama and suspense and then absolutely nothing happens.
They never mention Barbara and Adam even though they're supposed to be stuck in the house for decades and they helped raise Lydia. This was the weirdest thing to me.
Long pointless musical numbers used up time I'm assuming they didn't know how to fill with actual plot.
The actor who played the father gets a bizarre amount of screen time despite all the things he did in real life. You'd think they'd do a brief mention of the character at the beginning and then just move on, but, no. They made this real awkward.
Lydia went from a cool, confident, and brave teenager to a wimpy and mousy adult who gets frazzled easily and doesn't stand up for herself. Really odd and totally out of character.