Your asolute best of use of mile in southeast asia for a trip like that is US airways + BA Avios. US airway's chart in SE asia is a steal. 20k for economy, 30 for business and 40k for first class. If you have the miles, you want to go for first class as you can hit up the A380 on Thai between BKK and HKG, then you can hit up the 777-3 SQ first class from HKG to SIN. US airways allows one stop over or one open Jaw but you can make it better by booking a roundtrip and droping the last leg to create one stopover and one openjaw (this is how you get out of booking award ticket that involve two regions). For example, SIN - BKK(stopover) - HKG - SIN. Drop the SIN segment and you can visit 2 cities in one award ticket. This award is also cheaper because US see this award as a 1 region award. If you fly first class and exit BKK you get a free 1 hour full body massage at the airport (Business class get half an hour shoulder massage). Then use your Avio to fly on CX to nearby cities. You will have to pay a small amount of YQ if you use Avio on CX