Why not just mention the nationality; eg Chinese, Korean, Thai,Vietnamese etc

oriental seems fine to me

Yes this is generally true. "Oriental" can be used when referring to objects, while "Asian is used to refer to people (even animals). I don't think it comes off as offensive to the person be spoken of, as much as making the speaker sound ignorant or hopelessly old-fashioned.

From answers.com: "USAGE NOTE Asian is now strongly preferred in place of Oriental for persons native to Asia or descended from an Asian people. The usual objection to Oriental-meaning "eastern"-is that it identifies Asian countries and peoples in terms of their location relative to Europe. However, this objection is not generally made of other Eurocentric terms such as Near and Middle Eastern. The real problem with Oriental is more likely its connotations stemming from an earlier era when Europeans viewed the regions east of the Mediterranean as exotic lands full of romance and intrigue, the home of despotic empires and inscrutable customs. At the least these associations can give Oriental a dated feel, and as a noun in contemporary contexts (as in the first Oriental to be elected from the district) it is now widely taken to be offensive. However, Oriental should not be thought of as an ethnic slur to be avoided in all situations. As with Asiatic, its use other than as an ethnonym, in phrases such as Oriental cuisine or Oriental medicine, is not usually considered objectionable." I'd like to know whether this article is true.

Is not in the same way as you handle the "western" terminus?