Hi hun,
Its addictive this isnt it

I personally would take yoga instead to help you become more felxible. I did ballet for years and im now struggling as I have to unlearn all my ballet habits. Ballet lends itself well for the grace and posture etc to bellydance but the stiffness of ballet can give youer hurdles when you try and progress onto the whirly hip grooving bellydance moves. But....you might be ok as you will be taking BOTH classes...all I know is i have to really untrain my mind of ballet postures and movments!!