Oriental is more precise than Asian. "Asian" properly refers to all people of Asia including Israelis, Palestinians, Iraqis, Kurds, Iranias, Indians, Turks, Pakistanis, Afghans, Russians east of the Ural mountain range, etc.
Oriental properly limits the description to the people of eastern asia (including their descendants around the world) such as the Japanese, Koreans, Chinese, Vietnamese etc.
But when referring to people, the correct term remains "Mongoloid" as that denotes the race not the geographical region.
For the same reason Negro or Negroid is more precise than "African-American", since the adjective "African" properly includes the Arabs of the Saharan desert and Mediterranean region. If the term "Negroid" grates on your ear, you can use "Sub-Saharan African-Unitedstatesian" to describe those of Negro descent residing in the USA (African-American is incorrect as "America" includes the entire hemisphere and is not limited to the USA - for example, a fellow of Moroccan descent residing in Argentina can be described is an African-American as well).
As for whites, "Caucasian" is an unfortunate description, since it is rooted is the mythology drawn from the Japeth character in the tales and legends of the Old Testament.