in ts4 the traits are like everything else, just set dressing. ts4 is the game of playing pretend, pretend your sims is this, pretend your sims is that, it gets boring. and the problem is not only on the evil traits, it's on all of them. the fault for this are both the AI and the emotions. they're poorly worked and don't seem to mix well with the traits system. emotions were one of the biggest features in ts4 according to devs, it was gonna make them smarter or something but i'm seriously questioning the level of judgement they have. the system is too oversimplified and easily manipulable, now sims are ruled by them. no matter what kind of sim you create, if it's angry it will be mean to everyone, if it's flirty it will flirt with everyone and their mom, if it's happy it will be kind even with their enemy, if it's sad it will go cry under the bed regarding the traits you give them. and don't get me started on animations, they're all the same for every sim! how are the sims going to be unique if they all act the same? i've been playing ts2 & ts3 these days and the gameplay difference is huge. they're far from being perfect games, but if you make a lazy sim you get a lazy sim guaranteed.