Your perspective assignment is off to a great start, I think you've got a good understanding of the lesson.
There are a couple of things I think might help with your gestures. First is to think of the figure being made up of "C", "S", and "I" lines, and really try to avoid using the "I" line as much as you can. That should help give your figures a more flowing quality. Second is to not rush yourself, really focus on getting two or three lines down. When you see a large curve trace it out in the air couple of times before putting the pen down.
Hope that was helpful, your other stuff is looking good so keep at it!