The feelgood aspect isn't really from the various stupid deaths.
The film is about a hematophobic detective, Michael Burrows (played by Fiennes) who has a gift for making psychological profiles. He also has an unnatural obsession with the Darwin Awards. More specifically, he is obsessed with the notion that the people involved in them may all have something in common, and he'd very much like to figure out what that is. A cock-up during a serial murder investigation costs Burrows his job, which in turn gives him an opportunity to combine his profiling skills with his obsession by becoming a claims investigator for an insurance company (the premise is that these insane accidents--regardless of whether the people involved live or die--end up costing the insurance company millions every year, and it'd be nice if you could make reliable profiles for such people).
The focus is on Burrows' development from the obsessive, over-cautious, somewhat deprived detective to, uhm, something else
the Darwin-cases aren't just props for this element of the story, but the stupid/tragic deaths are by no means the focus.
Rather than cursing human nature, the film celebrates it (which was certainly not what I expected when I started watching). And, for being such a contrived character, I found Burrows to be very engaging!
The weakest part of the film is Winona Ryder's character. Or perhaps it was just her acting, I dunno. But it was acceptable!