In the time since this topic was started the issues of prejudice and bigoted language have certainly not gone away. Leaving aside the broader issues, discussed here and in
this topic, I feel two of the words raised by Tom,
dago and
darkie, should be classed as rare, based on recent usage levels.
When I was growing up the word
dago was used all too frequently in Australia to refer to Italian immigrants. But the word is seldom used these days - and when it is, it's generally in a historical context. And from what I can see the word is rarely used around the English-speaking world.
Darkie seems to be even less frequently used. So I'll make these words rare, along with the plural
dagoes.