I spent 1970-2 in PNG and had several field tours in late 70's. I probably accrued about 3 years plus in Irian Jaya between 1973-82. This was predominantly helicopter but often did positioning by either single or twin light a/c. In 1973 PNG to Irian was chalk and cheese. Mountains and weather the same but to all intensive purposes radio did not exist for SAR, wx checks or to fellow a/c by HF. In several cases companies would set up their own radio SAR but I suspect that risks were accepted as part of operating in a very third world country at the time. - this especially was a factor in doing long ferry trips across the more remote parts of Indonesia which equalled Irian in all but height of mountains. By early 80's Indonesian pilots were appearing as bush pilots but sadly the Asian pattern of thinking sent the least experienced as Twin Otter pilots to Irian whilst the more senior scored a relatively easy run from Jakarta to Sumatra at midday. I was out of flying by mid 80's but heard enough stories on PNG from people I still knew there to suspect the situation had almost reversed itself from fifteen years previously.
Perhaps limited and lightly administered ATC services would be a very useful way in which to offer foreign aid without raising the financial temptations that often occur