[Cola]

After so many positive replies, I feel rude for giving an opposing view, but if I were in your shoes, I would be worried about financial stability. I don't know your specific financial situation, so feel free to ignore what I'm saying, but I imagine that a police officer makes better money than your average English conversation teacher and would also have far better job stability and opportunities for career advancement and pay raises. And even if you don't like your job as a police officer, you could still easily switch to any other number of careers offering similar benefits in the U.K. In Japan, even if you speak excellent Japanese, your choice of careers outside of English conversation teacher tend to be very limited. Of course, you said you enjoyed being an English conversation teacher, but that brings me back to my main concern, money.

Of course, your situation may be completely different from what I'm imagining and you may have no financial worries for any number of reasons. It's just the main concern I would have as far as raising a family goes. Good luck, whatever you decide!