Yesterday night, I stopped reading a book which, quite frankly, bored me stiff with the many viewpoints of several family members and friends when it was basically the story of one main character and how she dealt with her boyfriend hitting her and an abortion. Unfortunately, I had to read her parents' point of view, her boyfriend's, her friends', her boyfriend's mother and if the author could have crammed even more into the book, I'm sure I'd also know the dog's point of view. The result was that the main character's viewpoint came far too short and missed the depth and emotions I'd hoped for. I wouldn't have missed any of the 'development' if those viewpoints wouldn't have been there in the first place. That'd be a good half of the book, I'd say. And it was a short book already. I do like character driven books, but if you chose to write such a novel, you need to go deeper. The book just scratched the surface, and as a result I couldn't connect with the characters. At all. In my opinion, the story would work great from two point of views: hers and her boyfriend's with flash backs into the past, to make the reader understand why both acted the way they acted. There was a lot of potential in that premise, but it didn't deliver.
There was also something I see in many new writers' manuscripts: the over-explaining of even the tiniest dust particle. If a couple goes for dinner, I don't really care what the waitress serving them looks like or what her name is. Unless she plays a bigger part or causes a particular reacting to the main characters, it's just 'the waitress'. Such minor characters can easily be cardboard cut outs as they don't need to stick with the reader. Better to concentrate on what's important: what does the restaurant look like (scene setting)? How do the characters feel (emotional setting)? What do they talk about (action)? Show me how they interact, their smiles, what they see in each others' faces? These are the things a reader needs to connect with the scene and the characters.
If you write a thriller, make sure to keep the reader on his toes. Place hints and move the plot forward quickly. Strip it from all unnecessary ballast, unless it enhances the plot and gives depth to a character. For example: a man visits a close friend in Paris only to find out she's a secret agent. He recalls some odd behaviour of said friend in the past. Or a woman is packing up her and her husband's belongings after she found him dead in their house. She remembers the good times. There is so much potential in such scenes and room for plenty of in-depth character development. Having the viewpoint of her mother, remembering how the couple met would be unnecessary fluff.
The main thing to remember is that a novel has a beginning, a middle, and an end. Everything should run smoothly into each other, without long-winded passages of empty scenes. All scenes should move the plot forward, or, in case it's a character driven novel, take the relationship to another level, push the thoughts of the characters closer to a solution.