I've noted previously that Dave Duncan is a usually reliable author (distinguished from predictable in that he generally offers an innovative concept), but that a previous book from Open Road felt like a lesser effort freshened up for sale. Unfortunately, all of that is true again for Irona 700.
Duncan again brings an interesting concept to the novel - mandatory government service via divine selection. His characters are as strong as ever - interesting, exemplary, and human all at once. The flow of the book is smooth (though in the first few chapters, the story lacks spirit). There's much more sex than is Duncan's norm - at times verging dangerously close to Piers Anthony levels of innuendo. Some of Irona's actions simply don't make sense in any context.
I could quibble that the book centers very much on in-world politics, but the fact is that Duncan handles it well, managing to make it interesting by keeping it personal. The problem is in the plot - there simply isn't very much of it. Instead, the book is essentially an interesting character of Irona - of the effect on her of politics and power. We've seen this many times before, but Duncan's skill with characterization makes the story both intimate and credible. What he misses is any real sense of purpose. The story starts, things happen, and the story stops. There's no sense of closure, and there are a host of loose ends and unanswered questions. It's interesting, but not satisfying.
A key question in the book is the mechanism of Irona's selection as one of the Seventy. We eventually learn more about it. And that's it. There's no further development, no action, no consequences. The same is true of Maleficence - an unspecified but evil adversary. There's a certain (disappointing) climax, but any number of issues left unaddressed, and one or two simple inconsistencies. It's conceivable that this is Duncan's intent - that he planned a stripped-down story focused on one individual. The placeholder naming (Benign, Maleficence, Irona) hints at that. If so, he turned too far toward toward subtlety. I suspect that the truth lies more in lack of polish than excess of purpose.
All in all, enjoyable, but not up to Duncan's past standards. If you're looking for an interesting slice-of-life exploration of the ways of power, pick this up. If you're hoping for wide scale world-building, try Brandon Sanderson instead.
There seem to be a few potential covers floating around for this book. I've linked to the one on Duncan's website, which is a bit basic, but better suited to the story than the others.