Well how about this: everytime the host changes the options, all the players in the lobby get a message containing what has been changed, and two options (actual buttons to press): ACCEPT or LEAVE. The host can start the game with the new options as soon as everyone has selected one or the other. No timed delay there, and if you're not fine with the new options, you can leave instantly, without a chance of the host starting before you've had the chance to leave.