Honestly, it's just straight up not possible to capture three beautifully written novels in one film, but they do a good job of summing up Tweak (the first half, anyways) and Beautiful Boy in a well crafted no-downtime two hours that left me fighting tears until I couldn't any longer.
My only complaint is that Tweak should have had a lot more screen time. I understand that it's a lot more heart-wrenching from a primarily parental point of view... but there is just so much more to the story than was portrayed.
Either way, the film did it's job. It was both inspiring and entertaining, and I'm looking forward to buying it for home viewing.