Coming off of the Wimpy Kid series as a spin-off centered around Rowley Jefferson, "Diary of an Awesome Friendly Kid: Rowley Jefferson's Journal" attempts to tell a story from the perspective of a different protagonist, only to flop miserably
The biggest problem with this book besides the writing for Greg Heffley, is Rowley Jefferson himself. Despite being appointed the protagonist this time, Rowley is still treated like a side character. The protagonist's role is to drive the story forward with actions fueled by personal goals and ideas. As usual, Greg comes up with all the ideas and plans to achieve his own goals, and Rowley continues to play as the passive best friend who goes along with whatever situation he's shoved into, with the only difference being that it's told from the latter's point of view and Greg is an even bigger jerk than usual. A passive character who lacks the actions and goals needed to push the story forward should not be the protagonist.
Since Rowley is not written like he's the protagonist, it makes the whole idea of this book pointless.
The other big problem with this book is Greg himself. This book is just so desperate to get a laugh out of its readers that it never takes a break from his juvenile antics. While he does get a few laughs at first, his behavior just gets so annoying after a while that it slowly renders him aggravatingly unlikeable. And since this is all the book is willing to focus on, it makes the book a struggle to read through.
This book could have worked if Rowley was allowed to have the ability to drive the story with goals and actions like Greg, the story focused on other aspects of Rowley's life instead of his friendship with Greg, and the comedic writing for Greg was more clever and less childish to make his mean-spirited antics actually funny.