@Snooty:
Actually, I'd debate a couple of your points.
Absent Minded can be horrible, especially in a large household. Forgetting what they were doing on the way to the bathroom could easily result in a shower that takes longer. And forgetting that they're headed for work? Yeah that can make it very hard to advance. But, forgetting that you're in the middle of cooking on the cheap stove can have tragic consequences.
Can't Stand Art not only gives a sim a negative moodlet when watching art, it gives them one when they're in the presence of it. It can help make for an unhappy sim in a well decorated household. And with free will on high, sims will look at paintings on their own (even if they have this trait). It elevates fun, although slowly.
Easily Impressed, among other things, makes conversations with snobbish sims a lot easier. But I do agree that it's not really of a whole lot of use otherwise.
Loser sims are far less likely to get instant promotion events at work, and they regularly have embarrassing things happen to them at work, which will wallop them with a pretty vicious negative moodlet.
Vehicle Enthusiast makes a sim a car fanatic.
Neurotic sims have quick and easy to get positive moodlets from freaking out and checking the stove or sink. Also, those little hand washing or teeth brushing wants are easy to fulfill for some quick lifetime happiness points.
Technophobe is easy to live with if you gear the house to accommodate them. You can do this by making sure you have separate television and reading rooms. They're also extremely convenient to have around if you're trying to complete the Electrician skill challenge for Handiness.
Coward sims will pass out when they see a ghost or a burglar, and the latter can be really bad if you can't afford a burglar alarm yet and they're the one trying to call the police.
Hates the Outdoors is an absolutely fantastic trait for a professional author.
Loner sims don't require as much social interaction, and their social bar drops much slower.
