Looks like many of the cruise out of Shanghai are just four or five night and most seem to only visit Japan... South Korean is right there, but on the site I checked out... no one was sailing to Korean. Several of the seven nights just did an extra stop in China or Japan.
I think Philippines, Vietnam, Thailand and beyond are out of the question unless they do 14 night cruises or longer. Or if they do a destination cruise where you sail to another port making a stops on the way - this really looks like the best option if your really wanting to see differing parts of Asia. Seabourn had a 22 night from Shanghai to Singapore with at total of 16 stops. Just have to wait and see what Disney plans to focus on with their itineraries.
To me a four or five night cruise... doesn't really give you much time to get your internal clock reset so you can enjoy yourself. It's one thing to travel to a city, that never really sleeps. But a ship? It's pretty dead on current Disney Ships at night... For sure would need to add on a few extra days to adjust before boarding.... of course with
Disneyland there and the likly hood of Land & Sea packages, that might be a viable option.
Not hating on the Adventure, just it's location (time zone changes, long flight, costs) makes it a tougher call for most of us.
I'd go ahead and book the Treasure.... and once the Adventure is open to booking, you can change at that point if the Adventure meets you desires.