Out of sheer curiosity: How do your brush your teeth? One night, when I was brushing my teeth, I came to realize that this has got to vary a lot from person to person.
With a manual brush, I brush the top of my teeth 20 times per "row", 10 times on the inside and 10 times on the outside (per "row"), then I brush the back of the innermost teeth a few times. After experimentation, I've come to the realization that this is my personal sweetspot, more than this and my gums suffer, less and I get terrible morning breath.
I could probably floss more often, and intermittently use mouthwash.