Here's a question- do you think this role was originally cast for a Polynesian performer? A cursory look at Wikipedias notable performers of this role I'm seeing Black, Mexican, and mixed race mostly. I might agree if the role was ALWAYS traditionally played by an Asian specifically, but I'm not seeing that tradition here. It wasn't written for an asian,  it was written for a woman. To cast an asian would be gravy but it sounds like its just not feasible.