my first guess was that you could barely make DM. I then did a quick estimate and confirmed my thought...your travel pattern could take you anywhere between 70-100% of what's required for CX DM. while for AA, you can easily reach 100-150% of what's required for EXP.

on the low end, assume:
- 4 HKG-YYZ roundtrips in J each year (~78,100 Club Miles or ~93,720 AA EQP)
- 4 intra-Asia roundtrips in Y each year, assuming 1,000 miles per flight and 1 AA EQP per mile (~8,000 Club miles or ~8,000 AA EQP)
TOTAL = 86,100 Club Miles or 101,720 AA EQP - i.e. ~70% of DM requirement but reached AA EXP already

on the high end, assume:
- 5 HKG-YYZ roundtrips in J each year (~93,720 Club Miles or ~117,150 AA EQP)
- 5 intra-Asia roundtrips in J each year, assuming 2,000 miles per flight (~25,000 Club miles or ~30,000 AA EQP)
TOTAL = 122,625 Club Miles or 147,150 AA EQP - i.e. just barely reached DM, but almost 50% above AA EXP requirement

so based on what you said, and assuming all your BIS indeed on these CX flights only, you can only reach CX DM only if everything is at the high end (5 instead of 4 YYZ-HKG trips, all intra-Asia trips in J, each flight has to be long intra-Asia flights at ~2,000 miles, etc)...

but, of course, maybe some of your existing CX Y flights are on discounted economy that don't earn AA miles...for those you actually would earn more with CX.

in your case, I think it makes perfect sense to stay with AA EXP rather than getting CX Gold...(that's my situation a few years ago too, most travel on CX, can easily make either CX Gold or AA EXP - and I went for AA as well).