The novel was not mostly flashbacks - the Kira side of the story alone was at least 100 pages. Really the only flashbacks that I can remember are Kira watching "Emissary".
By "Kira" I suppose you mean Keeva, or whatever the Bajora woman was called? This was the "short story" I mentioned. I call it such because it had absolutely no bearing on the rest of the novel. (Minus the last sentence)
Still, the first third or so of the novel is flashbacks. Then more flashbacks are sprinkled in the rest of the way. It's just not good storytelling. It's the first time I've ever been angry at a Trek author, before I even get half-way through a book.