Southeast Asia forum

I'd say the five weeks you have for China is plenty of time - but staying in Tibet for three weeks may prove expensive as the regulation to have a guide with you and stay as part of an organized tour. Things may change, but since 2008 there have been regular closures of Tibet and each time it "opens" for foreigners there are more regulations on where you can travel. The areas of Western Sichuan are very Tibetean (such as Tagong Grasslands) but not easy to reach and sometimes closed as well. Otherwise, depending on what exactly you want to see in China . . . Bejing, Shanghai, Guilin/Yangshou, Lijiang are some of the main highlights for people, I'd say you want 3 weeks minimum for any 3 of those 4 locations - also thinking that you could if going to Yunnan Province (Lijiang) head directly into Laos or if you pre-arrange a visa go from Guilin into northern Vietnam overland.

With 1 or 2 weeks in each country I think you'll want to focus more on a region - such as not Laos, but just Northern Laos and not Vietnam but Northern/Central Vietnam sort of thing. You must really want to see Borneo, and I'm into that - but if I was making this itinerary I'd probably cross it out as getting there and out will be very expensive and you could instead add that week of travel to the mainland of SE Asia. If you are really looking for some buddhist experience, you'll find some very heavy stuff in Tibet, but for a more smiling and cheerful approach to it I recommend more time in Laos.