This may be a little off topic, but another reason to leave long term is the impending degradation of the expat housing allowance. Read between the lines of the latest crew news when NR talks of 'when does an expat become a local now that someone may be in HK for up to 30+ years?' You can read this as, 'we want to give you a full expat package to 15; maybe 20 years, and then cut it down to a flat cash rate, say around 24000'. The implication of his statement is that you shouldn't qualify for an expat package after a certain time period. This is a typical CX divide and conquer strategy as you can expect they will offer a flat rate to local package SO/FOs at the same time. For those of us in HK I would recommend to get your place payed off then get a base ASAP. If you come back to HK for a captaincy then you clearly risk having your housing allowance pulled from under your feet when they negotiate further 'improvements'. This of course will allow the company to hire DE captains on a local package as they won't be able to get people to come back to HK as captains.
While I am not sure that Korean is the place to go, I think crewsunite is on the money when he says those of us who have missed out on the command bonanza of the last 20 years should certainly have a Plan B that does not include CX.