I loved the masquerade ball last year! It was a lot of fun even though I was probably the worst dancer, haha. We didn't get to make it to the lessons before hand but it was still a good time. Not doing a specific cosplay for it, just changing from my Tetra clothes into a dress and a mask. Would definitely recommend going!
OniCourseMusha, that sounds like a really awesome panel. Fantastic idea, I'll try my hardest to go to that as well!