I don't think J2 is anywhere a candidate and I don't understand why Skytrax gave it a 4-star after my recent flights on J-class. Seats are just angle flat for B767 and even within the same cabin, I find over 1/3 of the seats recline less than the others. FA distributed meals randomly without asking my choice, though if you asked, they would serve your request. Amenity kit is minimal. Heard B787 has better seatings, but now they call it First Class, and the PEY has become J-class with better food and J-class service. However, given the price they charged, I am more than happy to fly them again.
I agree with prior post that certain point of time down the road, MU may be out of ST given all the senior official/management changes in China recently. However, this may not be the top priority.
By the way, I recently received email from DL, promoting its deeper partnership with MU. DL members can now earn higher tier points when flying MU