RE: Heavy Rain - Hmm.... I always associated the Perfect Crime with the ending where the killer gets away with it. I guess though the antique shop changes on how much evidence is left and I can't recall how that changes the ending or not (it's been over a year since I did everything). All I do know is that is needed to be replayed from Hassan's through doing all the correct things and items in it would cancel the other two trophies you need.
Re: Noire - Yeah, I read the descriptions on the Social Club website and they're all hidden away in places or sitting beside things you probably wouldn't visit otherwise. At least it's only 50, but I hate fetch quests - especially ones with little to no payoff.