Your right Mr Train, I do think where your from has a bearing on your fave loco, it depends on what you saw on a regular basis. I was very fortunate to live just 10mins away from Tyne Yard. So loco wise 31s, 37s, 45s, 47s and 56s were the main stay down there, so 37s and obviously 47s became big favourites.
Sadly I only caught the diminishing years of Deltics but I remember standing on the bridge at Tyne Yard, you'd hear the infamous rumble of those Napier engines in the distance and it would stir a bit of commotion among those gathered at various points on the bridge. Sadly they were all too infrequent and disappeared completely only to replaced by Mr Granges, yellow and blue screaming MONSTROSITY.
My mates n I hated the HSTs or trams as they were nicknamed, I have no explanation as to why they were nicknamed trams, my assumption why, was because they could go either way, only the driver had to walk from one end to the other, just a modern day tram car. They later became zings, due to the noise they made when they went past. The 56s, aka Grids, made a similar screaming noise, hence me never being a big 56 fan too.
As regards Mr 13s topic of namers, I'm of the same opinion, as a kid, I'd look through my loco shed book, seeing locos with names like Isambard Kingdom Brunel, Robin Hood, Samson, Dreadnought, Superb, Peter Pan, Iron Duke, Hal o' the Wynd, Wolf of Badeoch, King Arthur, Howard of Effingham and Black Douglas, seemed to set the mind racing. A trip to Carlisle, not only were we going to see the leccys, the fact most of the 86s and 87s carried names, added to the excitement, hoping to see the likes of those was mentioned above. As it turned out, 86259 Peter Pan, was one I had to wait longest to see, it was my last 86 needed for sight, before renumbering got me not once but bloody twice, 86/4s then the 86/6s
At Tyne Yard, when a loco was coming, the odd shout amongst us would go up, its a namer, if it was a 47 with a white roof too, excitement would be fever pitch. Namers were held In such high regard then.
Some names were plain boring, normally carried by the zings, however Top of the Pops became a favourite, not because of its name but because when I actually saw it, on an afternoon Newcastle-Swansea turn, that left from a platform, at the Northern end of Newcastle that is now a car park,. 43002 Top of the Pops, was my last zing needed for sight, at last I thought, no need to look at these horrible things ever again. Of course renumbering bit me on the arse again.
Naming locos after a family of scallops, eg Pectinidae seemed pointless to me but it did greatly surprise my geography teacher, when I answered his question about if anyone could give him a collective name for marine life, when I answered, piscitororal, I erred with caution, pectinidae and Bullidae. I swear his eyes bulged and nearly fainted, especially when he asked, me to explain, what Pectinidae and Bullidae are please. When I said piscitororal was fish, Pectinidae is form of scallop or oyster and Bullidae are a form of snails, he was gobsmacked, as were some of my class mates, one whistling before adding, bloody hell listen you. My Geography teacher said to the whole class, 3 years I've been teaching him and whilst he's dumbfounded me on numerous occasions, for reasons known best to him, in 30 seconds he's just restored my faith in education.

All because those in charge of the Petroleum sector, decided to name locos, dragging their oil trains with silly names.
As regards the locos nicknames,
03, 08 ,09 and 13s were just shunter, wasn't till about 10yr ago I heard the phrase gronk, for the first time when I got speaking to a lad whilst I was on an overnighter at Carlisle. He was on a 2 week ALR and said he'd roped in over 60 gronks in his first week. I had to ask what he meant by gronk.
20s were choppers
25s were rats. 26s and 27s McRats
31s were Goyles or Peds
33s were Cromptons, Baggies an abbreviation on Bag pipes for a 33/1 and slim Jim.
37s were always were and still are Syphons, in my book at least, the term tractors was never used amongst my friends and I, tractors is a term, that seemed to gather pace in the last decade.
40s were whistlers
43 are zings or trams
45s and 46s were either Peaks or Wagons
47s were Duffs and I know people say its a derogatory name for them, it's always been a term of endearment in my book.
50s were hoovers, although I heard the term Logs used for them too. I fear that was certainly a derogatory name given to them by duff bashers.
56s were and still are grids
58s were known as Bones, for reasons, I'm sure someone will tell me.
59s and 66s, are Sheds.
60s are tugs, again for reasons best known to others, who will no doubt explain later, maybe its because they sound like boats.
67s are obviously skips
68s are Cats and 88s clockwork Cats, the pantograph being like a key.
70s I've heard plugs, mainly cos of the light set on their fronts or cos they're plug ugly.
73s were EDs
81s-85s were roarers
86s and 87s, I can't ever remember having a nickname.
The 89 was nicknamed the badger
90s were skodas
91s maybe nicknamed differently but my friends and I always nicknamed them Blunts, I still do.
92 were always Dysons.