Agreed.

To be honest, why bother having both Y-8/9 and Y-30 (or Y-XX) classes? If anything, the eventual goal for introducing Y-30 (or Y-XX) should be to succeed and replace Y-8/9 in terms of role and capability.

The Y-8/9 has a max payload of around 25 tons. Y-20 has a max payload of around 60-66 tons. Introducing a brand new airlifter just to fill the middle 30 ton-payload range niche would be very wasteful, which is why neither the USAF nor the RuAF is pursuing it.

Moreover, 30-35 tons offered by the Y-30 (or Y-XX) isn't really that much of a huge increase from the ~25 tons offered by Y-8/9. So there really is no good reason to justify building Y-8/9s once the Y-30 (or Y-XX) is ready and entering serial production. The max payload range offered by Y-30 (or Y-XX) is more than enough to cover the payload range offered by the Y-8/9.

Therefore, the Y-30 (or Y-XX) should be aiming for max payload capacity of around 30-35 tons, i.e. almost on par with the Kawasaki C-2 and Airbus A400M.

TL; DR - 3 tiers of strategic airlifters should do for the PLAAF:

1. Y-30 (or Y-XX) will succeed Y-8/9 and covers payload up to 30-35 tons;

2. Y-20 covers payload from 30-35 tons to 60-66 tons; and

3. Y-50 covers payload bigger than 60-66 tons.

[snip]