Hi Strangerdoom, Not sure this adds much to my earlier answer, but you never know

...
I first got PR about 8 years back. I was rejected on my first attempt. They'd made a mistake in the process, so out of a little guilt they gave me a few hints about 'why' (very unusual). On this occassion, my application was basically ok, but they seemed to have filled a quota. They suggested that if I reapplied 'straight away' then the timing would be good to get into the next 'quota'. Lo and behold I was accepted 2nd time around without changing a single item on my application.
As I mentioned, I believe the process has become smoother, faster and (pure speculation) more likely to succeed, in recent years. I hope so, because my wife has just applied

!!
Most (admittedly anecdotal, unproven) factors that help/hinder are not really in your direct control ...
- Education. The higher and more valuable to Singapore's positioning in the world, the better
- Race. Don't kill the messenger, but it's widely believed that certain races/countries are more welcome than others. I won't say more!
- Income. Again, widely believed but unproven, the more you're paid, the more they'll take in taxes, therefore that's got to be a plus
I hope this helps. Please get other opinions too, since I may well be wrong/out-of-date.
Good luck