Something rather less tangible that I will miss is the relative safety here. Of course with the North Korean situation you cannot say this country is so safe but this is only a background danger.
Having lived in the North of England I can clearly say that South Korea is far, far safer. Back home crime affects so many people that it's likely that if you've not been the victim of a crime you are in the minority. Here I walk the streets at all times and feel safe. There is none of the aggression that you can feel in the UK. You take it for granted but the fact is this country is much safer.
Of course there is crime here. Back in 2008 someone burgled my flat but left most of the things that I thought were important. Crime here is less on the surface and I am oblivious to most of it because it is less visible. People stop their cars, leave their engines on and go into the convenience store to get something. That would NEVER happen back home because someone would take the car. I don't feel as if anyone would even consider mugging me but in England I know I will need my wits about me and be careful with possessions such as phones, cameras and MP3 players. I am going to miss this security when I leave.