I think you'd have to let people pick a country per event, and not lock out countries once they are picked. There is simply too much variance between the haves and the have nots to only allow one person to pick one country, or one letting only one person have a particular country in a specific event. When it comes to things like hockey, youre going to have several contenders so people will naturally seperate themselves anyways. Score points 3 for gold, 2 for silver, etc., and keep a running total from event to event.