Neutral Terms for "White People"
My closer Chinese friends do use the terms 白人 and 白种人 neutrally in the same way we use "white people", but by and large I find Chinese people avoid these terms, and are set slightly on edge when I drop them casually into conversation. One friend told me she doesn't use 白人 because "听起来有种族歧视，不是吗?". Instead she and other Chinese usually use "美国人/法国人/英国人 etc." to indicate whiteness, but of course this can lead to some politically incorrect statements：

A: “你的朋友是华裔吗?” ("Is your friend ethnically Chinese?")
B: “不，她是美国人.” ("No, she's American.") [actually she's both]

Or this one:

B: “是不是美国人和黑人之间发生过很多冲突?” ("There have been many conflicts between Americans and black people, right?") [as if the two are separate groups]

In both examples, I'm fairly certain that the speaker is using "美国人" to mean "白人". Most Americans would take offense at this definition, because it subtly implies that non-whites are not true Americans, even if the speaker didn't mean it that way. Ironically, it is the avoidance of the term "白人", not its use, that causes the political incorrectness.

So, to answer your question, I think "白人" or "白种人" actually is the most neutral term possible for "white people", despite the fact that it seems to make most Chinese people slightly uncomfortable. Neutrality aside, 老外, 洋人, and 鬼佬 all refer to all Westerners, not just whites. And I don't think any Chinese people would self-identify as "白人" because of their skin color, except jokingly.