The longest journey starts with one step.
If there are fatals that can be attributed to the trip back with patient, then fixing that part of the journey is still needed. (One of the last fatals - doing a missed approach to an airfield 'cause they couldn't get into the hospital)
Remember if you can create precision (GPS) approaches to a hospital, isn't that the most common destination and therefore needs to be dealt with?
I like the idea of having pre detemined routes, but again it comes back to your Area of Ops.
Good luck gents.