Demand? there's always a demand for inter Island, Coastal-island hops, just needs a good advertising team and GOVN support. the public has to get over the "what?~! you want me to get into that little plane on pontoons??!" mentality too. tourists will be ok with it, I think.
the PT6 turbines uses Jet A fuel, no need avgas.
even a turbine Otter/Beaver will do wonders, they can be STOL fitted.
there must be a nich market somewhere~!
look at the terrain in Sarawak/Sabah, it looks similar to British COlumbia, Canada~!
maybe I am going nuts....