How about a slight modification of the original proposal.
First, decide on the number of riders (180 maybe?).
Second, the defending champ gets an invite. After that take the top individuals as was proposed earlier, but cap each country at 9 or 10. Just keep moving down the list until you get to 180 riders.
Once the numbers are set, if one of those riders passes on the event, then the country can choose any replacement they like. But if those riders WANT to ride, they can't be excluded because it doesn't fit the plan of their country.
First, decide on the number of riders (180 maybe?).
Second, the defending champ gets an invite. After that take the top individuals as was proposed earlier, but cap each country at 9 or 10. Just keep moving down the list until you get to 180 riders.
Once the numbers are set, if one of those riders passes on the event, then the country can choose any replacement they like. But if those riders WANT to ride, they can't be excluded because it doesn't fit the plan of their country.