Are you adding a little tuck or windup with your leading shoulder when you go for the three? A little wind up helps. Also are you spotting your landing by looking back at the booter or down at the transition you're landing on. Don't forget to use your feet and ankles to help snap you into the spin. Sometimes too much upper body rotary on small spins can throw you off balance. And using more of your feet and ankles will help you from setting too hard an edge as you carve up the kicker. Practice some crisp, flat-ground ones with little upper body rotary and a good knee bend and even pop. Do these at a good speed for a run and then come back and hit the kicker.