I would love to see speedcubing at the Olympics. As I read the criteria for new Olympic sports speedcubing fits perfectly.
As to qualifying for national and international tournaments, I'm all for that too. You should have to qualify for each event, though, not just as a good speedcuber. The same way that somebody can't qualify for the 100 meter sprint and just because they qualified they can also run the 400 meters and compete in boxing. They may be perfectly qualified, but if you want to compete in 4x4 you need to qualify for 4x4, not just 3x3.