The commercial traffic has always preferred to land south to the terminal and depart north from the terminal. Weather conditions allow this the majority of the time.
My wife and I witnessed this over the 25 years of flying our 172 Cessna out of this airport. And we live on the North Shore of Orcas just East of North Beach Road. Many mornings as we drink our coffee and look out towards Sucia, we watch a caravan on a 3-mile-plus left base at full cruise for final and also often the same on long right base. Bottom line is that our taxiway is not used very much by commercial airplanes. The windiest weather months here are normally November and March. The airport has the most activity in the summer and late spring and early fall.
Why not prioritize improving the main runway and pushing taxiway separation out to the future? Why not put an airplane traffic sensor on the taxiway to count the activity events? The reason given for expansion seems to be the wingspan of the Caravan. Is any consideration given to stall speed? Cruise speed?
Maybe for this amount of dollars, a relocation of the airport to Crow Valley would be far less expensive and be fully compliant to the FAA guidelines. The Eastsound Airport will never be fully compliant.