I have really loved the books I have read by Luceno before, so I was really looking forward to his take on Rogue One's lore. Catalyst focuses on Galen and Lyra, Jyn's parents, as well as showing the perspectives of Krennic and Tarkin. 
 Despite the high-intensity stakes the book moved very slowly for me, the interesting tidbits of lore scattered through very dry prose and frustrating character decisions. It was the literary equivalent of watching the characters pacing around in circles for hours and I felt it could have been cut down neater to make the events more concise. I struggled to keep interested despite the goings-on themselves not being boring... At least not on paper. There was just a struggle to become emotionally invested in the characters themselves apart from perhaps Krennic. I have a feeling Luceno finds his strength in writing more grey/villain characters and his skills as a writer shone less when filling in the perspectives of the morally good Galen and Lyra, who tended to feel a bit more stilted in their roles throughout the novel. 
 I did feel this added a lot more to the movie in terms of context however, so I do recommend it for those wanting even more information for the Rogue One experience. The extra insight of lore for this Star Wars era did make it a good read for me in other ways as well.