This is a great thread and theme. Joan's fascinating career can be divided into several phrases: MGM years, Warner years, 50s melodrama years and finally 60s
Grande Guignol years. Most seem to agree that the 1945-1952 Warner period was her peak. What is so interesting is just how completely different her MGM and WB phases/personas are. It's also a testament to the studio system and shows how every studio had its own, distinctive look, feel and style.
Joan made her Warner debut in 1944, in Hollywood Canteen, a Bette Davis vehicle dedicated to the war effort, along with dozens of other Warner stars and contract players. It was a nice way to welcome Joan, but her future was still uncertain at that point.
This was followed by a spectacular career comeback, when she had an amazing hat trick with Mildred, Humoresque and Possessed, all of them critical and box office successes. I think she looked the best in Humoresque, that movie is stunning visually and Joan's beauty seems to peak there. The final scene of her walk to death on the beach is haunting and inspired Madonna's Power of Goodbye video.
Joan's loan to FOX, for Daisy Kenyon in 1947, is a sort of middle point of her Warner years and represents a bit of a departure. I love this movie and it's a shame most people don't know about it or don't really care. I saw it 2 times and it strikes me as a bit of an oddity, in both Joan's career and 40s Hollywood. Joan plays a very modern, independent woman, who almost dates two guys at the same time and is torn between them. It's quite mature in its depiction of relationships and it's certainly not your typical 40s melodrama, there's more to this movie and some of the small twists and turns are quite surprising. In a way it feels like 1940s, post war Sex and the City. I hope some of you give it another chance.
Back to Warner's lot, and the second phase of Joan's era which is, as already noted by many here, seedier, trashier and in a way, more fun. Now she's clearly a bit older but she's still playing young women, she's been around the block and is damaged, but still wants to be a romantic ingenue. These sort of contrasts and contradictions are what makes these movies even more interesting. Flamingo Road is a fan favorite, Joan goes blond (as seen in my avatar), playing a small town carnival dancer (wtf) fighting the fat man himself , Sydney Greenstreet. Sort of a trailer-trash Mildred!
The Damned Don't Cry!!! It's 1950, and Joan is about to experience a career highlight. It's not necessary her best movie, but it's certainly a culmination of everything she ever did in movies, all the struggles, all the rags to riches stories, all the criminal hijinks, romantic melodramas and bitchslap moments. It all seem to collide perfectly in this movie which is a must see for any Joan fan.
After such an exciting height , it's hard to keep it up, and for the next two years Joan is on a slow downward slide at Warners. Goodbye My Fancy, is actually good imo, I enjoyed my one viewing of it. Maybe cause it's something so different and normal, after all the drama of her previous movies. It was time to relax a bit and apparently it's the kind of movie Joan wanted to do more of.
This Woman is Dangerous!!! But she's not damned.... and she's a bit tired.... And that's how this movie feels like. It attempts to go back to the criminal, edgy Joan but it just can't match her previous efforts. It's still a completely fine Crawford vehicle but at this point it's clearly time to move on. Joan knew this and so she did, leaving Warners and starting another successful phase in the 50s.
An honorable mention goes, of course, to Harriet Craig in 1950. Another loan out, this time to Columbia and perhaps Joan's scariest character ever. Not just that menacing hairstyle but the psycho inside is sure to leave you wondering.....
.... and lets not forget Warners also gave us Joan in glorious technicolor! It's a Great Feeling!