I've read a few of C. J. Cherryh's other books, and been only moderately impressed. Visitor changes that impression for the worse.
For one thing, so much is emphasized. I hadn't realized how odd that could be, but it seems as if the characters, when they do speak, are extremely emphatic, even about little details. The characters themselves didn't entice me much, and the cast could in some ways be summed up as elves in space. That is, a circumstance in which most of the humans are shown to be selfish, crude, and ignorant, while the elves (the atevi, in this case) are high-minded, wise, and thoughtful. The one exception being our narrator, who, while human, lives amongst elves and follows their standards. It's equally disappointing that Cherryh defaults to a standard set of gender roles - males run pretty much everything, except for one mostly off-stage human, and, of course, the stereotypical dowager who is sly and wise and runs things behind the scenes.
To be fair, this is a late-series book, and I've not read the prequels. Cherryh makes an effort to set things up, but it's not much of an effort, and it's not enough. The book is impenetrable, and even by page 100, I had no real understanding of who the factions were or what they wanted. It's a book in which very, very little happens - it's almost all musing about political machinations as they prepare for an alien visitor. If you haven't read the prequels, you won't follow it, and, worse, you won't care. If you have, I presume you'll like this; it's clear that previous books were just as complex. For a newcomer, the book only begins to be interesting in the last 50 or so pages. Everything until then is just long-winded, neurotically introspective setup.
The ending would have made a good chapter in a more active novel. The book as a whole, however, was far too slow and stiff to catch my interest.