I believe it’s hard to write a story if a character that we knew so much already. It is especially complicated when there is a big fandom, that will probably pick up on any non-canonical issues that may arise from some retconning or new information that doesn’t match what we know.
This is easily what I was fearing going into the story of Roku. But Ribay managed to surprise me, telling me about this new island and its powerful inhabitants. I also really enjoyed how we get to know more about Sozin, and his journey into becoming one of the most horrible fire lords out there.
By going to Rokus beginning, we get to learn about his training to become a new avatar, while also have some room for original stories. I believe the trouble to not deviate much from what it’s to come in the next century in the story of the avatar can damage the intensity of the stories we get to know.
While this book was pleasing and entertaining enough, it is not the joy of reading the Kyoshi novels. But it definitely makes for a better read than Yangchen. I juts hope future novels actually tell us about other avatars completely separated form the anime series (Muriel seems to probably have a very interesting story, which could be a one shot instead of the 2 novels per characters we’ve been getting). Other previous avatars can be even better… who was the second avatar, for example…