Those are great! on the engagement one, I love the song Barbara Ann, so I ask the audience to raise their hands if they know anyone named Barbara or Ann, and invariably there's a hand raised, then I say, well you gotta sing along when we get to chorus ... and Bam! they sing along and have fun, repeatedly singing Barbara Ann over and over again.
And then, connected to the Smile section, keep going, don't stop when there's a mistake, just get back up on the horse and continue!
And totally agree with keeping dead air to a minimum, I learned that one from watching the ramones.
PS: I think a fan blowing golden locks of hair would be totally cool!