If you can't provide proof of your intention to return to Canada (job offer, housing, etc), then at least you should be showing proof that you are beginning the process of cutting ties with HK. There are several things you could do, for example, shipping quotations, selling your business, pet relocation contract, future plans for employment for both you and your wife, and so on.
I have a little of both. I have a job offer, letters from my parents stating that we can stay with them until we sort out our housing, e-mails from mortgage specialists and realtors enquiring about purchasing a house, mention that I am a registered student at a Canadian university, my wife's plan for employment, and a very detailed account of all the things we need to do when we first arrive in Canada. On top of all that, I am sending an updated package to the HK visa office with more plans for our relocation, including: signed and stamped pet relocation contract with paid deposit, shipping quotation, flight quotation, detailed relocation budget, more detailed plans, schooling plans for our son, and so on.
I figure that they must understand that we can't completely cut all ties until we have confirmation on the visa. The only two things I cannot do at this point is quit my job (I am the only one with an income - my wife stays at home and takes care of our son), and buy our plane tickets.
You have to imagine as though you were in a court of law. You are the prosecutor. You must prove beyond a reasonable doubt...I think all of the above proof that I mentioned should be enough...who would honestly think I am going to live out my years in mainland China?? I have a job waiting for me in Canada that is a lot better than my current situation, so of course I will leave...but not just that, we are doing this for our son, as we refuse to raise him in the mainland (personal reasons).
Anyway, hope this post helps you guys...
FS