I've lived in UK, USA (Knoxville TN), Denmark, Netherlands, Japan and now Thailand.
Hard to define best.
US was fine and I still visit a lot.
Denmark was fantastic - but fkin cold in the winter
Netherlands was also fantastic but the Dutch were a bit cold
Japan is a beautiful place and a cultural experience second to none but after a year I couldn't wait to leave
After 15 years in Thailand, the place has worn me down - the crime & corruption is dragging the place down and I'll leave when my son reaches 16 or 17. It was fun.
Not sure where next. Australia is wonderful but I day trade US Futures markets and it's a shitty place to be for that with the latency and time difference.