Since most students from your school go to college in the US, wouldn’t the best source of information be the school? An international IB school in Asia is not a typical US public school, and I suspect most posters cannot give accurate advice concerning your son’s GPA etc. I read on CC that a 3.6 from a public school is not considered that good, but I know a 3.6 from a rigorous boarding school is considered very good. So it depends on the school.
Also, the financial side of things becomes important, I believe especially now. If you are full pay, that will make a difference to many (not all) schools. If you are looking for financial aid, or merit aid, that will affect the schools you would want to be considering.