Miss N Out:
Mass start race, with designated or x no. of laps where the last rider to cross the line is out until a final three, two or one is the winner. Sort of like musical chairs - the goal is not to come in last.

I'm supposing for our purposes, we'll have something like every two laps, last person to cross the line is out until there's a final winner.

Stands:
You guessed it, trackstands.

Chariots:
Awaiting 165's response. I know how they work with real Chariot racing - not sure how they apply to track exactly.