Thailand forum

cambodia is a great option and definitely something you could manage in those six days. flying to pp instead of siem reap will save you money, and then you could overland the rest of the trip. as cool as those places are, just a few days each should be enough to get a good feel for them.

since you mentioned laos, if your budget allows, you might also consider flying in and out of luang prabang for your six days. that would be a rewarding and relaxing time.

if you were thinking of staying more around bangkok, six days on samet island could be fantastic, particularly if you arrived mid-week and arrange your accommodation before the weekenders arrive.

i might also consider just hanging out, splitting the time between kanchanaburi and ayutthaya. great history, ruins, and food options. plus it would be a less expensive and less hectic possibility.

let us know what you decide to do and drop a line telling us about the experience. sounds like fun. regards.

Ditto the recommendation for Cambodia and several days in PP and Siem Reap. See the temples before they start having hot air balloon flights over them, or laser shows.