Among many other failings, the dramatized versions I have seen completely skipped over the character of Bishop Charles-François-Bienvenu Myriel--a monumental failing. Hugo devoted the entire first fifteen chapters to him and his character. He is one of the greatest characters in all literature and certainly one of my favorites.
I think even to begin to tell this magnificent tale adequately would require something like 20 or 25 episodes, maybe more.
I've read the book, and like it for things like that. Translating them to the screen, even at Game of Thrones scale? A challenge, at best.
Sir Cedric Hardwicke did pretty well with his portrayal in 1935.