Oh wow, Bly Manor is amazing. I’ve not seen Hill House (I will be watching it after this though!)
Just finished the 5th episode, it’s all been that perfect balance of mystery and scariness. Some of the accents at the beginning (and throughout) are a bit dodgy (just get British people to play British characters if you can’t get people that can do accents) but it’s worth persevering through that. It’s properly special.