To Voodoo:
What is your total length of stay in SG? You mentioned been employed on an EP from your own business for the last 3 years. Is that your total length of your time here?
Essentially PR is a route to full citizenship and so the criteria for granting it revolve around the likelihood of you wanting to become a citizen.
If you've only been here for 3 years, from ICA's point of view, it is probably too soon. (Preferred race candidates, particularly those from Malaysia, can be the exceptions to this. Although we have seen some surprising rejections here.)
Next they will consider how well or likely you are to integrate and become a part of Singapore society. Contributing/volunteering for social causes doesn't count anymore as this was abused in the past. Buying a private
property is equally meaningless to them. As a Caucasian, they may make the assumption that you are less likely to 'integrate' and may not be planning to hang around long term. As well as employing Singaporeans, does your business serve the local market or is most of it overseas? This is something they will also consider.
Bluntly, if you marry a local your chances will go up - but only after a sufficient length of time has passed to ensure that this is not a marriage of convenience. Producing cannon fodder for NS will also get you a good tick mark.
Unfortunately, your age will play against you: You are 46 now. You meet the (Singaporean) woman of your dreams tomorrow. You get married almost immediately. You will need 5 years of marriage under your belt (plus one or two Singaporean kids) to 'prove' that you are genuine about being part of Singapore society. That will take you to 51 or 52. Hmm...
To be very honest, I think you need a Plan B (as we are fond of saying here.)
"Both politicians and nappies need to be changed regularly, and for the same reasons."