One thing I keep in mind while trying these is to rotate from the bottom up... meaning it starts with the half cab style sweeping pop, then your hips follow while you flick, and the last thing to come around is your shoulders. I noticed if I don't think about controlling the rotation from the bottom up, I tend to miss the flick.
Another thing that helps me when I do them is to shift my weight more toward my flicking foot and leaning slightly heelside just before the pop. I think the biggest trick is getting the timing down and for you, probably trying to lighten up on the flick and flicking out like you said. Watch Bobby DeKyzer do them over and over, then go out and try to use those mirror neurons!