Queen Michael said:
Regarding point 1, and the "look" of a character, I would prefer not-so-realistic-looking characters over something like Polar Express, where the characters are so deep in the Uncanny Valley that I'm surprised any children that watched it could sleep after that without waking up screaming. They look creepy as hell, dude.
Besides, I can't think of many (well, any) good live-action movies that don't break at least one of these rules, and the enjoyment or childishness of a cartoon or movie isn't related to these 5 given concepts.
That's not to say that I wouldn't like a good, serious, animated film, only that, for the most part, the live-action equivalent would just be better, if realism is the only concern, in the way that a guy in an alien mask is better by nature than crappy CGI (AHEM Star Wars).
Take Paranoia Agent, for example. It's a pretty deep psychological anime (only 13 episodes long), but it contains elements of the supernatural, in a weird way. It's certainly not aiming for realism, either, and shatters your 5th point. The other 3, though, it fits quite well, and in my opinion, this movie would work almost as well as a live-action movie. It swears where appropriate, and has dark comedy woven in but is not itself a comedy. It certainly doesn't sound childish when described (a kid with a golden baseball bat is putting people in hospitals and some detectives are on the case, though there's something interesting about every "victim"...), though my description surely doesn't give it justice.
It's an adult cartoon that doesn't focus on sex (which is REALLY refreshing for an anime), and would work perfectly fine as animated or live-action, but I don't see how cartoons following rules 1 and 5 of yours would be at all enjoyable compared to the live-action counterpart. Some things just make more sense as live-action and some make more sense as cartoon.