How high do you tee the ball? Is at least 1/2 the ball above the clubhead? If you tee the ball too low, you will have to hit down on the ball too much. This will cause you to have too high a spin rate.
Too much backspin causes the ball to stop. As a drill tee the ball real high and try to leave the tee in the ground. You can do the drill with a 4 wood also. After a while you you will not get too steep on downswing. Don't break the tee in half. Hit golf balls; not tees. Remember, the right shoulder should move toward the ball on the downswing and the head should not move forward until well after impact. You want an "around-ward" pivot. Make certain you keep your spin tilt axis.