Chiming in from Sweden, I also loved flying as a young kid. These days I'm a parent myself and have sent my kids on flights (domestic only) using Unaccompanied Minor services several times, and it's always worked out well.
BTW, in Sweden the age limit for using this service is 12 - if you're 12 or older you're considered old enough to fly (again, domestic) alone, something my 11 year old daughter who turns 12 in a few months looks forward to as the last time she flew alone she felt that she was too big to've been "babysat" on the flight.
Yeah, you're right, I just looekd it up as well it would appear that "12 or older" is the cut-off now for most places. Ah well, those were just better times for air travel.
BTW, in Sweden the age limit for using this service is 12 - if you're 12 or older you're considered old enough to fly (again, domestic) alone, something my 11 year old daughter who turns 12 in a few months looks forward to as the last time she flew alone she felt that she was too big to've been "babysat" on the flight.