Most Europeans and a few others (40-45 countries) can visit China visa-free now. Many of them get 30 days entry. If your country isn't on that list then you can still enter visa-free for 10 days provided you fly on to a third country. People from 55 countries can do this. So you'd fly from Bangkok to Shanghai, for example, then on your way back you'd fly to Hong Kong or Tokyo or any other country except directly to Thailand. Just buy two tickets home. One to Hong Kong and one from Hong Kong to Bangkok. My husband used to enter on the 10 day plan and fly back via Hong Kong or Vietnam, but now he's on the 30 day visa-free list so he can buy direct return tickets.

My husband got his DTV on the advice of Thai immigration at BKK because he was going in and out of Thailand so frequently. He told them that his company is in Dubai but he goes back and forth to Thailand when he doesn't physically need to be in the office in Dubai. For the visa application he had to show all the required documents, but also he wrote a cover letter explaining his work situation that when he has time off he prefers to come back to Thailand and while here he communicates with office staff and clients online. Maybe you could include in your letter that while in Thailand you would be corresponding online with people at your work. It's worth a try. Not everyone has the same work situation so don't listen to people on this group chat that claim to be certain that you wouldn't qualify for the DTV.