Welcome to FT!
How often do you fly? Do you have any other travel planned on either Singapore or some other Star Alliance carrier in the near future?
What do you hope to use your frequent-flyer miles for? Short-haul flights? Long-haul flights? In Economy Class, or in a premium cabin?
Many European- and Asian-based FFPs charge hefty cash surcharges on award tickets. United's MileagePlus program does not; Air Canada's Aeroplan program does on some carriers, but not on others.