While I'm a bit new to the scene, but having been to DOs at SIN and TYO, I thought, how about HKG? As an ex-local, I can do most of the ground work and possibly lead a day trip or two as well.
As for dates, probably end of Q3 or start of Q4. It's just after the typhoon season, with the weather starting to cool down and less likely to be humid and/or raining. The Columbus Day weekend in mid Oct comes to mind as a possible date? (Not that HKG celebrates it).
Anyway, it's just an idea at this stage. Drop a post here if you would be interested in HKG, and if I get at least a few yes's, I'll put it into motion.