The Four Factors of what I look for in reading a book

I’ve grown into a niche of reviewing books the last couple of years, culminating with me joining both the crew at The Functional Nerds and SF Signal to do that.
So what do I look for when I read a book (especially one I am going to review)? Glad you asked…

There are 4 Factors I look for. I’ve mentioned them before, but let’s codify it.
What’s the story, Morning Glory? What happens during the book. I need action and adventure in the books I read. I don’t want to read a pastoral story about a hausfrau living on a farm in the 1880’s. I want a plot that carries me through the book, and away from the mundane world.
Who’s the protagonist? Who is the villain? Are there shades of grey. I want someone to root for, and someone for them to strive against. Neither has to be black and white, but I want a character interesting enough that I want to see them take on the world.
Make the world come alive. Be it a faerie-tinged Minneapolis, a fantasy kingdom with airships, or a steampunk 1860’s London. I want to be immersed (but not overwhelmed) with the details. Make me believe in the world you’ve created and that the characters are a part of it.
This is a tricky one. This is the one that brings very good novels that have the other three and bring it to the sublime and best novels. Language can range from Hemingway to Wolfe in terms of style, but its often a “x factor” in my reading.