I was going to say 'great questions - looking forward to the answers' that's my sort of trip too.
Was your no-go mainly based on the logistics with the time frame? If yes, were you only looking at 'major airlines'?
Any other info as to why no go?
The decision to delay this little adventure was mainly based on timeframe available, what I wanted to see, connection times and a change in time I had available. I had to move my departure from AU back by a couple of days, this became the first problem. This reduced the available time frame from arriving in SIN mid afternoon on 29 May and wanting to be back in SIN by mid afternoon on 6 Jun. Some of the challenges for each location.
Tibet. You cannot travel outside of a tour group so tour group dates was a factor, there was the option for private tours however I was not interested in that. The original idea was to catch the train from CTU to LXA and fly back. The train travel time is approximately 37 hours and trains depart every second day and for the dates I have available this would not work. I then considered giving up the train and fly into LXA and discovered that to board the aircraft you need the original visitors/travel pass to board the aircraft, in addition these are not sent outside mainland China and they can be sent to the hotel. Initially I thought I would be able to fly into CTU go landside to a hotel collect pass and back airside, about a 6 hour layover, tight but most likely doable. The tour company strongly recommended against this and suggested that I stay at least 1 day in CTU. A side note, to travel by train you only need a copy of the visitors pass which I was informed can be emailed to you. The tour I was looking at was 8 days so the timing did not work. There were shorter tours however these did not allow time to do the things I would have liked too or see. For the dates I had available tours seemed to start on either a Wed or Fri and I could not work in with these schedules. I will go to Tibet at some stage but will allow around 14 days from leaving AU to arrival back in AU.
Bhutan - Like Tibet unaccompanied travel is not permitted. Unlike Tibet I found that the time I had available may have been sufficient as Bhutan seemed to have more flexibility in tour dates, costs are a little higher as the daily fee charged to tourists is regulated by the Government (USD250 per day) however most meals are included. Flying into PBH seems to be easier than getting to LXA but involves other connecting flights and from what I have read is limited to daylight arrivals and departures only. From the 3 locations Bhutan was most likely my lowest priority.
Mongolia - Time was the biggest factor here, flying into ULN is not difficult you just need to travel from certain airports. There seems to be a few things I would like to see in Mongolia and I think the time available and time of year was the biggest factor to exclude Mongolia. It can be difficult to gauge length and time required for travel and I suspect that Mongolia is larger and may take longer to travel through than I anticipate. It is a place I would like to get to and I considered it when I attend the Lounge crawl in HKG in 18, time was also an issue as well. I will go at some stage but may plan it as a trip rather than an add on.
At this point in time if I can make some more time will reconsider Tibet, my fallback position will be a 6-7 days in Taiwan.
This trip was a bit of an afterthought as I was already going to be in SIN and time available is the biggest constraint. I still plan to go to these places but will do so when I have more time. I will do Mongolia as an individual short trip. I may combine Tibet and Bhutan travelling Chenghu-Lhasa by train, join a tour that covers Tibet and ends in Nepal and then fly to Bhutan as a single but slightly longer trip maybe 14-16 days.
We have a bit of travel already planned for 2020 so not to fussed if these places get moved out.
