Yes, that's a good idea for the Americans to qualify, but most people from other nationalities can't play those tourneys and the only one they can play is the monthly International Open.
I think perhaps it would be better to use a method that is available for both teams instead of having different methods of qualifying, because otherwise there could be complaints that one method favours one team or the other.
As for the Captain, I think he or she should be someone that volunteers to do it, not the one with the best score, because the Captain will be required to make the pairs for the Alternate hole and the Fourball (though he can take advice from players who want to play together) and I don't want to give anybody that doesn't want it any extra work.
But keep those ideas coming, I love it!