I like your idea.
However, I would like to keep the national tournament. Let's say, we should have a continent cup every 4 seasons, and we should have a world cup every 4 seasons. We could have the national tournament in other seasons.
Season 27: National Tournament
Season 28: World Cup (First 2~4 rounds of National tournament would be used as qualifiers)
Season 29: National Tournament
Season 30: Continent Cup (First 2~4 rounds of National tournament would be used as qualifiers)
Is this revised idea good?