A lot of the critics seem to disagree with me*. Sure, another writer could have taken the same characters in the identical situation and come up with something a bit more incisive. What we have here is a slice of life with at best, only the outline of a plot, yet I found the characters engaging enough not to rue seeing them pushed into profounder situations.
Emily Blunt in particular gets a great deal out of the simple details, and it is as a rather coy collection of these that Sunshine Cleaning ought to be judged.
* Stephanie Zacharek in Salon for example: "Sunshine Cleaning is something like Little Miss Sunshine, in that its quirkiness has a facile, efficient quality. It has nothing of the openheartedness of Juno (a quality that softens even the aggressive cleverness of Diablo Cody's script). So how you'll feel about Sunshine Cleaning probably depends on your tolerance for slender, semi-hip comedic dramas about oddball families grappling with sometimes overwhelming problems." and Roger Ebert: "This is promising material. Gene Siskel loved movies about what people actually do all day. There is even a documentary subject here. But not this film that compromises on everything it implies, because it wants to be cheerful about people who don't have much to be cheerful about. How can you make a feel-good movie about murder-scene clean-ups?...You won't have a bad time seeing this film. You may get a little frustrated waiting for it to take off. It keeps heading down different runways. There's a movie here somewhere. Not this one."