Do you think that the Weasley parents were modeled after Mr. and Mrs. Bennet from "Pride and Prejudice," since JKR is a big fan of Jane Austen? Arthur as the laid-back father and Molly as the harried mother? Because if so, then I think that JKR missed the point.
Because Rowling is a BAD WRITER if she retroactively failed to write characters according to the exact pattern of other characters you personally find similar.
Personally I find it hard to imagine Mrs Bennet taking out Bellatrix Lestrange or knitting a Christmas jumper every year for a lonely friend of one of her children.
The Weasley children are not clones of Molly and Arthur, and raising a crop of smart kids willing to risk their lives for others in a wizarding war is not a sign of bad parenting in any universe. (Ron's OWLs were about the same as Harry's--he's far from stupid, as dungeonwriter seems to enjoy implying.)
uuuuuuuugh why do they keep bringing up all these Mrs. Bennet this Mr. Darcy that things from Jane Austen? God, if they had their way the Harry Potter books would be a bunch of books only adults read and which kids would think hideously boring because the bitter teacher always gets what he wants and ruins the students' lives at the end of every book.
The Bennet's were not good parents. They had 5 daughters and only 2 were close to what would be considered reasonable human beings. Mrs Bennet didn't have 2 brain cells to rub together and Mr Bennet only took time with Lizzy and Jane because they were the only daughters he gave two figs about. He got bit on the arse with this attitude and he did have the grace to be ashamed of it. Arthur and Molly are nothing like Mr and Mrs Bennet.