I just finished Mutiny on the Enterprise last night (TOS #12), and I have mixed feelings.
The Enterprise, being overdue for some dry-dock time where repairs can be made and shore leave can be taken, is ordered to the Orion Arm to oversee peace negotiations between two systems. There is a Romulan threat in the background if the negotiations fail, so off they go against Kirk's and Scotty's better judgment. On the way, they pick up a young lady named Lorelei.
Lorelei, a pacifist who has the unique ability to influence anyone (except Spock and Kirk, it seems) to her point of view just by talking with them, begins to lead the crew to believe that their mission will start a war and should be avoided at all costs. Her activities cause all crew members to slack in their duties. The engines go out and the Enterprise becomes little more than a sitting duck. Luckily, she is in orbit around a planet that has supplies they can use to repair the ship.
Kirk has to find a way to get his crew back under control, get the supplies off the planet in spite of extreme danger, get to the peace conference before war breaks out, and still keep the Romulans at bay.
On the one hand, the story was fun and believable. Other than the Spock-McCoy banter happening a bit more than usual and being a bit forced at times, everyone acted in character. And there was quite a bit of suspense. The pacifist message came through strong and was strongly squelched by Kirk.
However, the book had zero character insight or development. It read like watching an episode. Not even that well because visual description left something to be desired more than once. The events had little or no emotional impact on anyone, except Kirk being frustrated with the mutiny. All I'm saying here is that there was dialog and action, but little to no "getting in their heads".
The novel is still pretty enjoyable, and completists will definitely want to add it to their collection. But I don't think I would put it on the "oldies but goodies" list.