You're the interesting one, shivvy, so y'are. Your crowd usu say "whenever I was living in england" for "when I was living in england", even if they only lived there once. Did you consciously drop this practice? Perhaps because you became aware that it causes confusion in England? I'm not saying it does in NI, because the distinction is just not operating.
The reason you give for not being happy if called a 'mick' or 'paddy' is the standard one for all these terms. It is indeed their association (and not necessarily their combination) with other derogatory terms that may offend those so apostrophized and does offend those who insist on being offended on their behalf. (I am not denying that 'black ******* or for that matter 'fat *******' are more deliberately offensive that Buenchico's unadorned '*******' above.)
The case of Harry is moot: 'little ****' is only such a combination if you are on the qui vive for heightism as well as the weightism I implied above. Well of course the media are always on the qui vive for the poor boy's next crassitude, and he did make matters worse not better by adding 'friend' to the mix. Think of our Scottish friends in the Govt.
In a BBC discussion this morning there were certainly objections to 'Jock' as well, no doubt to the grim satisfaction of all well-balanced Scots. Like the well-balanced Irishman, they have a chip on both shoulders!
Being unbalanced myself, I don't mind being called a Pom in Strine, whether accompanied by 'whingeing' or no, and cannot understand people getting het up about such appellations on my behalf.
We English are not the only Brits, shivvy. Certainly you are, whether you like it or not. Dare I say that even the irredentists are inhabitants of the British Isles?