I read the books when they were first published and loved them, but the first episode of this adaptation was very disappointing.
It suffers from the BBC drama disease where everything feels slightly inauthentic somehow. As far as I can remember, the Gyptains in the books were a very distinct culture with overtones of old Roma beliefs. In this show, they are just the "noble poor" on boats.
Again, the world of HDM was very much a world of adults, with Lyra seeing events through a mistaken child's eyes. This show sets her up as a kind of Harry Potter character, and that grates on me. The books portray the idea that Lyra can do what she does because she slips through the net of notice because she is a child and adults largely ignore her.
Also the magisterium scenes feel a bit Star Wars, and I never got that impression from the book at all. The world is far more steam punky than the show conveys.