Thailand for sure is the most accessible country to travel to in South East Asia. It is very safe, has a pretty good infrastructure with many low cost airlines and you can discover it on a budget easily, without sharing your bed with cockroaches. Also it can be visited best during the winter time on the Northern hemisphere when generally there is a dry season in most of Thailand and the conditions for travelling and enjoying the beaches are very favourable.
At the same time Thailand is also a country with a long history and a lot of culture, being an independent Buddhist kingdom which has never been colonised by the Europeans (sharing this honour with Japan by the way, not the only similarity between these countries). When obeying some strict rules like respecting the king, who can be seen everywhere on pictures, you can pretty much roam freely in Thailand and the people are pretty open minded. Being transgender for example is not a big issue over here, the sight of so called ladyboys is pretty common. Thais are very friendly to tourists and of course some will see an opportunity to sell you something, but you are not a walking dollar bill like in other parts of Asia and Africa. Unfortunately still the level of fluency in English is not very high among Thais, especially the older ones, but it changes and some kind of communication is always in reach, may it be with a little bit of imagination or the help of google translate .