For future releases of CTA I would love to see a 2D physics engine implemented. So that animators could add things like snow falling randomly, or empty a container of bouncing balls and have them react randomly. And to be able to have gravity and wind apply to a character or prop. If gravity was applied to a character, i imagine rag-doll physics for 2D characters could also be applied. Then you could drop a character out of a plane, and have gravity and wind randomly applied through a sliding scale to affect his movements randomly and get different results.