The Chicago Manual of Style is useful for a lot of writing, especially more formal work, but most books are not that sort of material. Almost all of the writing I deal with [with which I deal] is personal writing; the tone is more intimate and person to person. I use three primary criteria when editing: 
     1. Will the reader understand what the writer is saying? 
     2. Will the reader get a sense of who the writer is? 
     3. Do the mechanics of the writing (spelling, punctuation, sentence and paragraph structure, overall presentation, etc.) enhance the content, or distract from it?

One of the things I avoid is making an article or book “my own.” If you will take a bit of a distanced look at most magazines, for instance, most of the articles read as if they were all written by the same person. This is the result of editing to match the articles to the magazine’s style, or an editor’s preferences. While this can create a personality for a publication (or a publishing house), I prefer to treat each book as an individual expression of its author. So I try to use a light touch rather than a heavy hand.

If you look at this website again, you will see my personal style of writing. It is somewhat heavy and dense, with what is to most people, I think, too terse a tone. I don’t think this style is appropriate for most authors’ work. But the alternative would be to impose an inauthentic style from a manual. I am not comfortable with this, nor do I think that authors would be.

I would be remiss if I did not make all the suggestions I felt were necessary or useful to communicate your work to the reader. However, as author and self-publisher, the final decision is yours, and of course, I will be happy to make whatever changes you feel best express your story.