Edmund Muskie, and the Canuck Letter.
CMC fnord!
Supposed acronym-based etmymologies like Worthy (or Westernised) Oriental Gentleman, Prisoner Of her Majesty, or For Unlawful Carnal Knowledge are almost always unfounded. Maybe we need a new law for this - GorillaMan’s Law perhaps, since it has he who I first recall making this point? 
Another term in this category is ''cracker" for a white person. While originally pejorative, and still often used in this sense, it is sometimes used self-referentially, and with a sense of pride, by some “Florida Crackers” and “Georgia Crackers.”
“Okie” may also be in this category, being pejorative in the 1930s, less so now.
I know there are some old words that were insults way back when, and have lost their spefically pejorative meanings over time. “Barbarian” is one such word – it was originally a specific Greek insult for those who didn’t speak Greek (to whom the speech of non-Greeks presumably sounded like “bar bar bar …”).
I’ve always been under the impression that those two acronyms were merely apocryphal etymologies of “wog” and “pom,” and that neither of them is actually the true origin of the word. Almost every Aussie dictionary i’ve ever read says that the origin of “pom” is uncertain. According to the Oxford English Dictionary, the most likely origin of the word is a shortening of “pomegranate,” and give some quotations in support of this:
Regarding the “prisoner” acronym, the OED says:
As for the origin of “wog,” all the OED has to say is:
I was going to say “get off scot free”, but when I looked it up, its got nothing to do with being a Scottish scrooge. Evidently the meaning comes from the old norse word “skatt” which means tax.
Thanks Usram and Mhendo , serves me right for listening to my good friend the drunken aussie git! 
(He also taught me to play Spot the Pom, while traveling across SE Asia. He was damn good at it too!)
The fact that you refer to it as “the n-word” implies is still has a lot of gravity!
I think a lot of it has to do with the relative position of the people being referenced. “Whitey” isn’t much of an insult because whites are (historically and currently) on top. Likewise, calling a guy a “bastard” is certainly an insult, but usually not taken with nearly the same weight as calling a woman a “bitch”.
So it would seem to be that the words you’re looking for are those aimed at people who were once much worse off than they are today. “Mick” and “paddy” are perfect examples, as are “wop” and “dago”. They may still be considered insults to some, but not nearly to the extent as “the n-word” or numerous slurs aimed at Latinos.
My old dictionary also lists “goy” as an “offensive” term used by Jews to describe someone who is not Jewish 
The Hawaiian term for people is kanaka. In the thirties, forties and fifties, this term was considered to be the equivalent of calling Blacks niggers. Presently, it has been reclaimed again by present day Hawaiians, usually as kanaka maoli - indigenous Hawaiians.
We are still working on whether Chini and Portagi are still insults. Kepani and Philipino, no longer are.
Etymonline disagrees - but it’s unfortunate that it’s hard to follow up its references: mick | Search Online Etymology Dictionary
I never realized Hottentot was a racial slur until it was pointed out on this board (and not from any recent thread, it was a while back). I honestly thought the Hottentots were a tribe. Ignorance fought there, for sure.
No, it doesn’t.
The only reference to Mick in the website you linked to is the word “Mick”. It makes no mention whatsoever of the phrase “take the Mick”. You do understand that phrases like “Take the Mick” and “Coon’s age” can use words without any racial implications?
Wasn’t “taking the mick” originally “taking the MICKEY?” I was told in England that it derived from Mickey Mouse, and doesn’t refer to the Irish.