Couldn't figure out where to post feature requests so I posted here.
Seems like a pretty basic functionality. Using the align property to align the container div is less than desirable. Would be best if there was just a default class added to the container div. Also an actual shortcode attribute class= would be nice for adding additional custom classes. They shouldn't overwrite the default class.
This would make cleaner markup in the editor instead of requiring people to wrap their own container classes to do special alignment.