Sorry it took me so long to chime in on this one. I've been working a lot lately and just trying to get myself back to my old ways again. So far it has been working out well.
As for NI and England. Though I have been to England a bunch of times, I can only really give my experiences on NI based on my living here the last 2 and a half years. Yes. The police stations are like fortresses. It was because of the troubles some years back. They aren't and never will be over but things here are a bit calmer than they were. It is a beautiful place unlike what a lot of natives here like to believe. We all take our homeplaces for granite sometimes it seems.
I do find it much more bigoted here rather than any other place I have ever known HOWEVER, people here once they get to know you are very friendly. Jobs are hard to get. Though I am in fashion/retailing, because it's a small country all around, they like to keep to their own and because they don't know the whole US expat thing, they tend to keep things simple for themselves. I did get work but with an American company. Go figure.
Food here is simple but I think that is the case with most places in the UK. I come from NY originally so my tastes are quite extreme. I do think the food they do make is quite good and prices are comparable or cheaper than most in the UK.
Accents are quite different here than the rest of the UK. That is quite apparent. Belfast has a more whiney accent than where I come from, but in my opinion, they have some of the most interesting accents in all of the UK although I must confess that Welsh accents are a fav of mine.
Sheep and cattle are the same here
I think the slurry thing may be the most annoying and apparent difference with the landscape. Even over the border of the republic doesn't have that stench like here. I guess they care a bit more.
As for other things, there are many and I am not sure where to start. I can say, I still love it here despite its many many problems. For now, it's my happy home.
If you want help or advice, give me a shout. I'd be glad to help