Hi youngoznomad,
I had the same idea around 13 years' ago, with the idea of spending 2 years as an English teacher in Hungary before travelling round the world, but have stayed put in Hungary (though not teaching anymore - 3 years teaching was enough for me).
To answer your questions, in my opinion:
- No, it's not a difficult job, but then the more you put into it, the more you'll get out of it....
- The "language barrier" is as difficult as you make it - I made a determined effort to learn Hungarian and it was worth it for me. It pretty much depends on how much you want to get to know the country/society/culture, how long you intend to stay, etc., but I'd say this depends on you and your attitude...
- As for wages, it depends what you're used to, but you should be prepared to expect a considerably lower salary than in the UK for example (where I arrived from).
As for advice, the main thing is to enjoy the experience and learn as you go along. I did a one-month TEFL as well, it was a big help, but it doesn't suddenly make you into a great teacher. Also there are (were?) plenty of opportunities to do private lessons in your own home, or wherever, including swap lessons (i.e. you teach English, they teach you the local language).
Good luck!