It's pretty straightforward: Will you use Diamond benefits the next year? Or not? Or uncertain? And how extensively will you fly CX metal ex-HKIA?

For someone like me, it's fairly straightforward provided CX doesn't do any serious devaluations or things that really piXX me off. Essentially it's their business to lose. My profile: Based primarily in Hong Kong, must fly through or ex-HKIA extensively (each month on average, I'll do more than one round-trip (departure/arrival) visit to HKIA per week), extensively visit many of the long-haul cities in CX's network, care about flat beds and quiet in the cabin, and there is a 0% chance unless I die or something crazy happens that this travel pattern changes in the next few years!

You should bear in mind the best use of Diamond I'd argue is someone who heavily uses HKIA because the lounges are fantastic and numerous, the ground benefits solid enough (assuming you have HKID card), the IRROPs help from staff is simply superb. If you're coming from a far-flung outport with just a frequency or two a day, less IMO.

If you're an outport base, or don't fly as extensively, or are really price sensitive, then I really encourage you to look elsewhere. CX's lounges have absolutely risen in standard, and the A350s are lovely, but most everything else sadly has gone downhill in the last 5 years. CX is fortunate they still have an excellent hard J and F product because even though they're no longer cutting edge, those products are so well-designed they do keep us sticky.

The other reason you keep it is it's a lot easier to burn Asia Miles as a Diamond member, period. So this might be helpful if you plan to burn a lot of Asia Miles in the next year or two.

Anyway, Diamond is far more expensive to earn than virtually every other OW Emerald status. Relatively speaking it is not an "easy" route at all to elite membership. As many other people alluded to it just may not be "worth" it, and I'll argue it definitely isn't worth it if you don't necessarily have to fly much CX the next year. For people in my shoes it makes sense....although CX is starting to walk on thin ice even with us.