This would be a very big ask of the most sophisticated and advanced aviation regulatory and training systems in the world.
I would bet folding money if the UK CAA, US FAA, NZ CAA or CASA got involved with 'regulating' PNG aviation matters the place would grind to a halt in a week.
PNG operators have always self regulated - I would argue for the most part quite well.
I think that Chimbu has pointed out the essence of the success of PNG aviation in that it is largely self-regulated. The PNG aviation environment is very hostile and extremely unforgiving of any misjudgment either from pilots or other aviation operators. So as in Darwinian gene pool theory, you make a mistake then that's all...Those that have the skill-sets are able to survive and make a go of it. Commonsense interlaced with lots of PNG experience is the only criteria that has proved to date to be a viable way to operate.
I would think that it would be nigh on impossible to write a comprehensive set of regulatory notes to cover all the nuances of aviation operations in PNG. And if it were possible, squadrons of lawyers still would not be able to understand and clarify those regulations let alone explain them to the operators so that effective operations could still be enabled.