Once you get the sound you want, stick with that setup. As far as subdivisions, play with a metronome. Set it low, and start tounging the same note, then gradually move up. Just like anything else on a sax, you've got to start slow and get the hang of it. Once you've got the feeling in your toung, and fingers, the speed as well as smoothness will come to you. Trying to jump too far ahead of yourself can only develope some pretty bad habbits.