But just to ask a question.
Why does it matter if the books are shallow? The only books that really make it anywhere are the ones who cater to people who have IQs equivalent to, or lower than, our President. Therefore I say enjoy the shallowness, get a good hearty chuckle out of how stupid they are, and move on.
I don't say this to tear down the fandom. I think fandom is wonderful. I think If You Are Prepared and A Bittersweet Potion are probably two of the greatest ... novellas, I suppose ... that I've ever read. And I have absolutely no problem reading too much into books and then arguing over them and stuff.
But really, those with an above average IQ have got to stop expecting too much from people. Subtlety is a tough thing to deliver, that's why its subtle. And it doesn't sell especially well, either.
I thought HBP was great, because it quickly covered a lot of things that I wanted to happen (lots of extra Snape goodness, and That Person Who Dies -- god finally!), without a whole lot of crap that I didn't want to happen. The middle was kind of boring, I'll admit, and it wasn't especially well-written, but to be fair, JKR is not that spectacular a writer on the grander scale of things. She is, however, very postmodern, and that's pretty in with pop fiction right now. Additionally, she's working on a deadline. She's under a lot of pressure from us, her fans, to get novels out and get them out NOW before we suffer serious withdrawal symptoms. Its basically impossible to write something really good without having time to think it through thoroughly.
Although the stealing from your own fandom needs to stop, JKR. That whole thing with Blaise Zabini was a cheap trick.