Predictablility in books...

so I am reading the book Brisingr, and it seems centered around the battle between good and evil, which is very typical of a sci-fi/fanstasy book. Last week I complained about how the main character of the book is far too perfect, well he was actually able to kill someone who wasnt fighting him, he killed a soldier who was in retreat from a battle. I am glad that this happened because it makes Eragon a more unpredictable character, which creates conflict and some supence in the novel. I do wish they did a little more explaining the antagonist because all they have really told you about the evil character in the book is that he once was good and now he is evil. This lack of an explanation about this character makes him not mysterious but very uninteresting.
Some things I do like about the book are that not ALL the characters are either perfectly good or impossibly evil (without explanations) some of the characters most notably Roran, Eragons cousin. Roran is a good character but he enjoys fighting in battle and getting revenge for the death of his parents (or something like that). The fact that he likes what he does adds character depth, and a little spice to the story. The world that the author has created is also very interesting, the author developed a complex mythology of magic and the magic language. The author makes all that deals with magic in this world very complex and many mistakes are made that result badly for those involved. This also adds a little bit of surprise to Brisingr.

Overall I would say my main complaint with the book is that it is woefully predictable, but in the end it is worth my time to read because it is a fun to read book.