I didn't really hate living in Japan. I hated working for a traditional Japanese company (you know with the old guys running it and not wanting to listen to your suggestions but expecting you to change things for the better, working 6 days a week 12-14 hours a day). Just not having a car, not being able to read everything, having a clothes washer that took 3 hours per load, (OK, maybe because I couldn't understand the directions
) stressing out from the culture. It was very stressful. I think Japan and the culture (even if it is stressful) is very beautiful. I made amazing friends, met my wife, did crazy things, and had fun when I wasn't working.
Teachers can make a lot if you are willing to work on your off time. But you'll miss out on all the best parts of being in Japan.