I will first say that I don't recommend DL's program if you are primarily interested in award trips to Asia. Switching to United will probably make far more sense given your priorities. However, contrary to previous poster, DL award levels are not actually unknowable. With some basic methodologies and techniques (using the Award Calendar and reading the Fare Rules), you can generally divine the various award levels on any given route even though they are not published in a chart anywhere.

To cut to the chase, there's no way you can get Delta One/Business Class from US to Asia for less than 120K miles each way with Skymiles (240K miles roundtrip). This is the current lowest level for both Delta One awards to Asia and partner Business class like KE Prestige (unlike Delta One and partner Business class to Europe where there are different award low level mileage amounts). There are somewhat lower levels for partner business class from Mexico to Asia at 90K each way (180K roundtrip), if you are willing to do some more convoluted repositioning. There also look to be 80K each-way business awards (both D1 and partner) for Asia to/from the Caribbean (like NAS). But again, more convoluted repositioning is required.

The best bet for finding Asia awards from the US are generally from the large west coast gateways like SEA, SFO, LAX. When you say SGP, do you mean SIN? If you are willing to fly coach, DL currently has 62K roundtrip (31K each way) coach awards for SEA-SIN and that's as low as you will likely find from any US gateway. From the award Fare Rules, these awards have roundtrip booking (can't be booked separately as one-way's), 30 day advance purchase, and Mon-Thu departure requirements.