I would say Thailand is one of the most promising destinations. I have been there years ago and I still have fresh memories in my mind from beaches, mountains, jungles, temples to Cities. I love each and everything about my journey. People are friendly but there are some certain rules you should be aware of such as removing your shoes before entering any house or shop. Wear a decent dress while entering a temple or a religious place. And avoid saying anything annoying for the king and for royal families. It is a cheap destination for tourists. We were there with a group of 20 people with an expert guide, however for solo travelers i would advise to be careful from scams and from accidents as traffic accidents are very common there.