With regards to these 10,000 teachers they want, this is what will happen, more white non natives will be hired from eastern and mainland europe, more indians who are on holiday will decide they want to stay longer and will come and get jobs (they tend to be very qualified anyway) in all areas, their only barrier is language sometimes. They already have some sort of agreement to hire more filipinos so this will be expanded and more will come over, unless the filipino government give the teachers that payrise they have been promising for a long time.
More natives will come with short term agencies such as media kids who will stay for four months and be replaced this will make the figures look good as well. But any natives with brains will do the maths and realise you can't do any travelling after your contract is over on these salaries and not bother. China pays a lot and even vietnam are slapping an extra 20,000 baht on salaries this is enough to save and have a good holiday when the chances come along. Holidays and money those are the real benefits of working ...if the kids are great to teach thats another benefit as well.
To get more teachers you need to up the salary modestly to 60k (many private schools could pay this). Offer a free flight home on renewal or not. Give a completion bonus like china vietnam so you can actually have a month off and then come back renewed and happy. I could go on. This is my personal experience of what is lacking after working in Thailand. After trying to go on holiday with my gf three times the same thing happens each time. Not enough money to do anything. Why do you think young teachers come here or even those in 30's and 40's its not to retire, they want to have fun and travel.
Thats how you get more teachers .. my advice get TAT to organise it. The best advert i ever saw had a sexy thai government teacher .. on page two of the website .. come work for us and get a sexy girlfriend .. classic