How do Chinese people feel about the term 非中国人 to express non-Chinese people?
In my opinion, 非中国人 sounds more exclusive. 非 stresses 'are not' (they are not Chinese)
外国人 sounds more neutral. 外国 indicates 'where ones came from ( they are from outside of this country)'

非我族类(其心也异) is not a friendly phrase

外賓 is a welcoming term


To me, 非中国人 (non-Chinese) VS. 外国人 (foreigner) is like 非会员 (non-member) VS. 访客 (visitor/ guest)
老外 is an informal nickname for 外国人. Sounds casual and friendly.