How can I make my look flatter?

First of all, most "good" quality leotards such as those by Capezio are made to be body hugging which means they will automatically hold your in and eliminate some of the pointyness and size issues. Also, they do make bras specifically for wearing underneath leotards for such situations. Just make sure you aren't doing your leotard shopping at like Walmart or somewhere but are actually going to a dance wear specialty store. They will be able to help you choose the most appropriate apparel for what you need.