I once had to use "reasonable" force to stop a first aider in the UK interfering in dangerous ways.
Ignoring the survival.kit bits, you should probably have
Painkillers, non prescription
Some simple plasters and dressings to cover the sort of minor injury you may pick up a any land away
For bigger things you can stop.bleeding and reduce pain fairly easily
Tourniquet
British type.modern first field dressing
splints of some sort
If you're in the Bush and not an expert with more equipment and drugs I wouldn't suggest airway devices as you either don't need them or the casualty won't benefit.