I think 'Vulcan's Glory' could be considered one of the worst. The story just doesn't seem to flow well and the characters don't have the same charm as they do in the TV shows or better - written novels. It lacks the sense of wonder and discovery that is typical of Star Trek.
I think 'Vulcan's Forge' is one of the worst. It had some really cheesy dialogue that didn't seem to fit the Star Trek style. The plot also had some holes in it. For example, some of the character's actions didn't seem to have proper motivation, which made the whole story feel a bit disjointed.
In my opinion, 'Dyson Sphere' is also a contender for the worst Star Trek novels. The science in it was a bit iffy. It didn't really hold up to what we know about the Star Trek universe's science. And the story was just not that interesting. It lacked the excitement and the thought - provoking elements that good Star Trek novels usually have.
Well, it's really subjective. But some fans might consider 'Spock's World' by Diane Duane as one of the worst. The plot can be a bit convoluted and the characterizations not as strong as in other Trek novels. It kind of strays too far from what makes Star Trek great in terms of its core values and the way the characters interact.
Well, opinions on the 'worst' can vary greatly among fans. One that often gets criticized is 'The Final Reflection' by John M. Ford. Some fans didn't like its complex and convoluted plot that deviated too much from the typical Star Trek feel. It introduced a lot of new concepts and species in a rather clumsy way, making it hard for some to follow.
The 'New Earth' series had its detractors. The plotlines in some of the books in this series were seen as rather convoluted. For example, some of the characterizations didn't seem to stay true to the original Star Trek characters. It was like they were trying to do too much with the new setting and lost sight of what made Star Trek great in the first place.
Definitely 'The Good That Men Do'. It's a great addition to the Star Trek Enterprise novel collection. It not only continues the story of the crew but also adds new elements and story arcs that are both interesting and in line with the Star Trek lore. The character interactions are well - written and it makes for a very enjoyable read.
Good Star Trek novels are those that can make you feel like you're part of the crew. 'The Entropy Effect' by Vonda N. McIntyre does this well. It has a great mystery and the characters are well - rounded. In contrast, 'Prime Directive' by Judith and Garfield Reeves - Stevens is often considered bad. It takes the concept of the Prime Directive and twists it in a way that makes it seem more like a plot device than a fundamental part of the Star Trek philosophy.
Well, 'The Crystal Star' is often regarded as one of the worst. It's got a plot that's all over the place. There are these strange alien concepts that don't seem to blend well with the rest of the Star Wars elements. It's like the author was trying to be too creative and ended up making a mess. The characters also don't act in ways that we've come to expect from them in the Star Wars universe.
Well, 'Aftermath' is often regarded as one of the worst. The story just didn't seem to have the same level of excitement as other Star Wars stories. It focused a lot on new characters that many fans had a hard time getting attached to. There were parts where the pacing dragged, and it didn't do a great job of making you feel like you were in the heart of the Star Wars galaxy.
A really good one is 'The Lost Years'. It's a great novel because it fills in the time between the end of the original series and the start of the movies. It shows what the crew was up to during that time, the challenges they faced, and how they continued to grow as individuals. It gives fans a chance to see a different side of the characters and their lives outside of the main events of the series.