On the character of Little Dorrit

Tom at Wuthering Expectations wrote 2 blog posts about Amy:  
http://wutheringexpectations.blogspot.com/2012/01/nobody-cares-about-little-dorrit.html
http://wutheringexpectations.blogspot.com/2012/01/why-i-care-about-little-dorrit-many.html 
I care about her, to some extent, but Amy Dorrit is still an insipid character.
Before any wandering Dickens hater jumps in to say Dickens can’t write believable characters and most of all can’t write women, I have to say that that’s not what I’m saying, and I don’t agree. Little Dorrit is populated with lots of fascinating, colourful characters—Mrs Clennam, Mr Meagles (“practical people”), Flora Finching (Arthur’s old flame, now a large chatty, insufferable woman), Mr F’s aunt (“a face like a staring wooden doll too cheap for expression”), Mr Merdle the merchant (“extensive bosom which required so much room to be unfeeling enough in”), his son (“his brain had been frozen up in a mighty frost which prevailed at St John’s, New Brunswick, at the period of his birth there, and had never thawed from that hour”), Mrs Merdle’s parrot (“broken into a violent fit of laughter, after twisting divers bars of his cage with his crooked bill, and licking them with his black tongue”), etc. These are the caricatures, vivid and believable in the Dickens world. 
At the same time, Dickens also creates the more realistic characters—characters with complexity and contradictions. William Dorrit, the debtor and the Father of the Marshalsea, is a good example. I went back to the beginning of the book and tried to find out what he was before going to prison, and couldn’t find the answer. What was he that allowed him and his children, except Amy, to think so highly of themselves and their family? So far I think he’s the most interesting character in the book, because he lives in such a bubble and refuses to see the truth and recognise his dependence on Amy. In him, there’s a mixture of pride (and false pride) with a deep sense of humiliation—he is aware of his position whilst trying not to acknowledge it. 
I sympathise with him—after all, degradation and humiliation is something I know too well. But I do dislike his self-entitlement, insensitivity, and selfishness. He thinks more about himself than Amy.
But to go back to Amy Dorrit, she is insipid. Too good, too forgiving and self-sacrificing, as people say, and self-effacing without a sense of self-righteousness. Does that not make her a 2-dimensional, saintly good character without flaws? 
Except that Amy has a main weakness—she does not protest, and allows the whole family to use and exploit her, to take her for granted. 
She also has pride. Chapter 20 is particularly interesting, because Dickens writes about the difference between Amy and her sister Fanny, and shows the 2 kinds of pride. In the chapter, Fanny brings Amy to meet Mrs Merdle because her son wants to marry Fanny, and she disapproves. Amy would be too proud to take money or anything from Mrs Merdle, whereas Fanny, because of pride, says her family is unfortunate but not common, sees herself as a different from Amy (for not being born in prison), and says she must make Mrs Merdle pay for being insolent to her family. That’s the difference between the sisters. But this would be the reason that Fanny would nurse that sense of being insulted—she would always be bitter because, in accepting the money, she allows Mrs Merdle to humiliate her and her family. 
I’m reading chapter 24, when Amy, or Little Dorrit, comes to meet Flora.
Will Amy become more interesting?