That setup would be fine, if someone were willing to pay for the twin on the contract. The government won't do it here, and there aren't that many hospitals which will, and those are used mostly for transfers, not scene flights. The question that always has to be answered is "Who is going to pay for it?". Bigger, more capable, and more expensive aircraft are nice, but who's going to pay for them? In the US, the answer is generally "Nobody". The current system here has evolved over the years, with little regulation until recently. Changing entrenched bureaucracy isn't easy. Another factor in the US is the idea, also firmly entrenched, that any company has the right to enter the marketplace and compete. The FAA is required by law to consider the economic impact of any regulations.
I'm not defending any of the above, just saying that's the way it is. Those in other countries are always free to do things the way they want, as the US will undoubtedly continue to do.