Scooby and Shaggy were always strung out on meth. And the new Battlestar (which is what I assume you're referencing) is only about 10,000 times better than the original. Not joking.
In all seriousness, you have a legit point. Trying to rework things that were inherently childish into adult concepts is going, oh how to put this gently, blow. So I agree, to a point. I just want you (and less you because I assume you know this) and everyone else to recognize 2 things:
1) Aiming a story at children is going to restrict your art. Are Wall-E and Up good films? Fuck yes, I loved them. Will they ever have as much brilliance and meaning oh what are my top 3 adult films, say Godfather, Blade Runner or A Clockwork Orange? No, never. Not their fault, but simply aiming it at a younger audience means you have to sacrifice some artistic merit. Want an example from the same director? Look at the difference in quality between Ponyo and Princess Mononoke. (And I liked Ponyo before I hear it).
2) You have to recognize what are already kind of adult themes. People assume that comics are inherently for kids, and that's not ENTIRELY wrong. But it's not entirely correct either. Batman, for example, is not an inherently childish concept. It is, when you strip away a lot of our assumptions, about a 10 year old kid who watches his parents die and, again boiling away a lot of stuff, goes completely off the wall crazy, dresses up like a Bat and starts punching criminals. Is it silly? Yes. Are there already adult concepts and stories working their way in? Oh yes.
Just some food for thought.