This novel is filled with cliches. Everyone is doing involved in something that is 'their last best chance' at something. There is a trial by combat, the annoying ambassador, the alien misunderstanding. It's all been done before, only better.
I thought it would be interesting to read a novel about Sulu as a captain, but in this one he is simply a cardboard cutout who smiles or grins at everything. No characterization worth reading.
Also, the story is told in third-person 'removed'. The only way to appreciate this annoyance is to watch an episode of the PBS kids show Calliou before reading this book. In the cartoon the narrator says things like "Calliou didn't want to take his medicine, but he didn't want to feel bad either." This is exactly how this novel is written. You don't read the story directly as it happens, no, you read a narration of the story (e.g. "Sulu didn't want to go to do something, but he felt he had to.") I felt like I was reading a book written for grade schoolers.
The big problem, however, is the stories logic and flow. At one point Sulu 'figures out' who the aliens are. How does he do this? Who knows, the narrator doesn't really explain but somehow he puts a couple of obscure facts together and amazes the reader with a warp-leap of logic. The whole story is like this, and it disappoints greatly.
In a nutshell, you feel like you are reading a loose translation of a story outline without actually being allowed to get into the story. Sulu does smile though.
Read any of the Shatner Trek novels, or New Frontiers novels for a much more enjoyable reading experience.