Thanks all to replies. I now understand better that the best use of KF points is with SQ Saver Awards indeed.
The trouble is, on the day I need to fly (3 months out from now) SQ has no Saver award available on SYD-SIN F or J class, only the J class is available for a non-A380 plane on Standard awards, which is 90K for SYD-SIN one-way.
I guess the best value is hard-to-get sometimes with only a very limited availability released at a time.
Also, my purpose of getting to PEK was to get to WUH later (SIN-WUH flights have absolutely atrocious timing for my schedule) so I am hesitant to add to many additional legs and make it SYD-SIN-HKG-WUH.