One step that the US is going to have to complete in order to be less restrictive on tourist visas is exit processing for international travel. Currently, the US has no way of knowing when a foreigner, or an American, leaves the country. Most countries to which I have traveled make you go through immigration when exiting.
I believe that the ability to instantly know when someone is overstaying their visa is a critical aspect of having more open border when entering.
One concern I have with Brazil visas is that you need to get them so soon before visit and they are not good for that long of time; many travelers get caught in a Catch-22. When China raised their prices, they made 90 and 180 and single and multiple entry visas the same price. I have not had any problems in getting my two Chinese visas and my entry permit into Tibet.
Paul, one question about your article. Why did so many people show up at the pier knowing they did not have a Brazillian Visa? The visa and Yellow Fever shot are very clear requirements for a cruise to Brazil.