Just got back yesterday from Breathless. Had a great time. We were there for 6 nights, and there wasn't any "theme" nights. There was a neon party on the beach Thursday night. A couple of dance shows in the upstairs theater. A huge beach party yesterday for the 4th. But no theme parties where you'd dress up. There were events scattered about, including live music, games, etc. If you have any specific questions, just ask.
Last year I saw a really attractive girl go topless. Needless to say I coined her the President because wow she was popular.