I really liked the story idea, and how the layers of "acceptable" behaviour are peeled one by one from the beautiful wife. Maybe if I had a harder time accepting that she really is that kind of self-indulging, egocentric and jealous woman, she turns out to be might have made the film way more exciting.
The film uses flashback technique to brace the actual story, but that didn't work quite well for me. Also, I think that the murder of the little boy in the lake could have been more haunting. Maybe Hitchcock should have treated this script - it would have made great sense within his own oeuvre.
Still there remain myriads of things in this film that I love. Foremost, the absolutely stunning photography, the colors, the nature, the sea. Everything looks really beautiful and the colors are breathtaking. Tierney is a must see, possibly one of the most authentic 40s beauty ideal I can think of. I remember hearing somewhere that she detested her high voice and took a lot of training to improve it - maybe that does show a bit.
Although the lake scene is more of a "casual" murder, its images still linger in my mind. Great rewatch just for that scene.