As stated above, the NTSB has no regulatory power of any kind. They just investigate accidents and make recommendations, which the rest of the world is free to ignore, and generally does.
The FAA has been very reluctant to regulate operators - see the Eclipse soap opera, detailed in the current issue of AIN. HEMS in the US is a commercial operation, and few officials are ready to use socialist-seeming regulation to force anything on the operators. In the US, anyone with some capital is free to try to make more by any legal, or even illegal, means, and if someone gets hurt or killed, that's regrettable, but just part of the cost of doing business. I don't expect much regulation in the short term, and perhaps more deregulation, especially if the Republicans can maintain their current Congressional seats and McCain can manage to win. McCain has historically been hell-bent on deregulation, especially for the industries he's been paid to help. A little bribery goes a long way with politicians, and it's totally legal in the US, as long as you call it a campaign donation.
If the Democrats win big, there might be some tightening of the rules, but I don't foresee all that much, because they can be bought just like any other politicians, and we have the best government money can buy.