What is the best frequent flyer / travellers award program for Asia?

It would take way too long to answer your question in this forum. There are so many factors involved. I've flown over 700,000 miles in the last six years between the U.S. and Asia, my best advice would be to choose the program from an airline that has it's hub in the city you will be flying to most often. For instance, if you fly to Hong Kong frequently, use Cathay Pacific's Asia Miles Program, if you fly to Bangkok, use Thai Airways etc.. Loyalty to a program has it's rewards, once you reach Platinum or Gold status, you will get priority check-in, boarding and baggage, as well as lounge access and sometimes complmentary upgrades. I would choose an airline that is either a Star Alliance or One World alliance member, as they are the two largest alliances and will give you the best choices of airlines and destinations. On almost all airlines and alliances you can upgrade with the airline that most of your miles are on, but not on other airlines in the alliance, but you can get award travel on any of the airlines in the alliance. I'm probably confusing you by now, so why don't you go to www.webflyer.com or another frequent flyer opinion website and maybe you can sort it out. Good luck!

I prefer KrisFlyer by Singapore Airlines

Try Mabuhay Miles of Philippine Airlines and Air Philippines.

It depends on what airline you always use. So I suggest, enroll with the airline you fly with. I use Mabuhay Miles for Philippine Airlines. I get free tickets to different destinations, depending on accumulated miles.