Wow, you've put a lot of effort into that post...
Anyway, I have a few recommendations for you, although some of them might be hard to find in your local takeaway, but I there's nothing all that outlandish. In general, there are about three kinds (regions and dim sum etc. aside) of Chinese food you can get in England. The first is that of takeaways, which is pretty much inauthentic and specific to England (and America?), much like Indian takeaways. Which is not to say it's all bad - in particular, hoisin duck pancakes are pretty amazing, and I like loads of the sides like mini spring rolls, and prawn toast (although this can be a bit greasy). Lots of takeaways also have a Szechuan section, which I recommend looking into if you like spicy food - the classic red sauce beef szechuan is pretty good:
It tastes far nicer than it looks - have it piled on top of a bowl of really fluffy egg fried rice for best effect. And crispy chilli beef, although note that it's sweet, chewy, and not really meaty enough to be a main:
So what of the other two types of food? Well, they both come from the more authentic places, which generally means sit-in restaurants. In particular you get a load of these in Chinatowns, but they're elsewhere too. Now, sadly most of these places are under the misconception that Westerners will only like bland food, so the vast majority of the menu will be rather dull, along the lines of "rice/noodles plus weakly flavoured meat and possible sauce." This is pretty different to the standard takeaway fare, and is generally a lot worse as it's just so flavourless, and the meat is often somewhat gristly. That said, I do like the honey roast pork that lots of these places have on the English menu, although note that it often comes cold:
Accessing the much better food that these places have is somewhat tricky then, as it's usually on menus they don't give you. Sometimes you can get hold of an English translation, although you'll have to ask specially e.g. for the home-cooked menu or the Szechuan menu or something. This stuff is generally all great, although can be very spicy. And in some cases the only way you can get hold of the good stuff is by ordering in Chinese, which only really works if you have someone Chinese/Chinese-speaking with you. There is this book however, which is designed for this precise problem. In general I haven't tried a lot of this stuff for obvious reasons, but I want to investigate more.
One other area you could look into is dim sum, which is a kind of Chinese lunchtime food consisting of loads of different types of dumplings and similar things, my favourite being char si bao, which are big cloudy buns of pork and win:
These can be hell to get hold of in England though. Some Asian supermarkets sell them frozen, and you can steam them, but I've only seen them available fresh in Chinatowns. Loads of places in the London Chinatown have them, although Ikyuusan (a Japanese/Chinese/Korean restaurant on Gerrard street) is the only place that serves them all-day, with most places only doing dim sum at lunch.
Anyway, those are my suggestions...