I'm sorry to say I wasn't impressed by Dodger.

It was an interesting attempt to write about the real basis for Ankh-Morpork, 19th century London.
We have many of the Discworld archetypes but something doesn't work and I don't think it's the less fantastic setting.

Dodger is simply invincible, there is no tension there is no adversity.
In a book about a suer rat making it big, there is no struggle there is no hardship.
Dodger's way to the top is paved with well intentioned adults that help him overcome any possible hurdle.
Dodger himself is perfect in every way, no one can challenge him if he gets into a fight, no one even lase a hand on him, if he wares a disguise no one notices if he breaks in to a house he can walk around as a pleases and no one will notice and if there is a chance of getting into trouble, he is after all a member of the wrong class in 19th century London... well there's always someone with serious clout to smooth the way for him.

I had a similar problem with Terry's latest Discworld novel
[b:Snuff|8785374|Snuff (Discworld, #39)|Terry Pratchett|http://d.gr-assets.com/books/1302694636s/8785374.jpg|13659124], Vimes has become too powerful and there is no sense that he may fail, that he is in someway an underdog fighting powerful adversaries.

Compare Dodger's journey out of the suers to that of the Rats in another Prattet YA book, [b:The Amazing Maurice and His Educated Rodents|34534|The Amazing Maurice and His Educated Rodents (Discworld, #28)|Terry Pratchett|http://d.gr-assets.com/books/1168566225s/34534.jpg|1179689]. Compare Vimes in [b:Guards! Guards!|64216|Guards! Guards! (Discworld, #8)|Terry Pratchett|http://d.gr-assets.com/books/1347382469s/64216.jpg|1128601] to Vimes in [b:Snuff|8785374|Snuff (Discworld, #39)|Terry Pratchett|http://d.gr-assets.com/books/1302694636s/8785374.jpg|13659124].
Yes Vimes is a developing character and does gain more power in each successive book he appears in, but I think that only in [b:Snuff|8785374|Snuff (Discworld, #39)|Terry Pratchett|http://d.gr-assets.com/books/1302694636s/8785374.jpg|13659124] did he become invincible.