What is your favorite genre isn't a simple answer for most. Depending on where you have been in your life, some appeal to you more than others.
Horror is struggling to become mainstream. If you aren't Stephen King you will be struggling to be recognized by mainstream publishers. I for one can't read a Stephen King novel, it become tiresome and boring. Waiting for something to happen takes too long to hold my interest.
I want to be hooked from the first paragraph or at least intrigued enough to continue.
Romance does good even in these hard times. Everyone needs a little hope and a solid connection between two characters.