I still feel frustrated with the UA and I would like to hear the opinions of others, maybe I'm missing something.
For Ancient-Classical era, the UA still feels like a much weaker version of uniques like Aztecs UA or Celts Morrigan pantheon. The UA is slow without the free XP from buildings or the AI's bonuses.
For the midgame, I find that what pushes Japan is the Dojo's promotion and pure conquest. Having a large number of puppets for free

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(which the Dojo stats help a lot) is relatively easy for Japan, and usually matters more than the UA's yields. Having Dojo + Samurai helps to get good yields, but falls off in relevance somewhere during Renaissance.
The UA can gain relevance again at late Industrial, with Military Academies + Branderburg Gate + Elite Forces + Orders belief, but isn't guaranteed. I think it can match the former "GWAM on Great General/Admiral birth" if accomplished, now that the iLevelUp = 5 means any new unit would give +70

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, but isn't something Japan is tailored to consistently get.
Overall, I still feel that the UA should be something different. I like the theme of "yields on leveling" for Japan, but I think the current scaling doesn't help enough to get started in the earlier eras, the reason given for the change in the May 22nd version (
https://forums.civfanatics.com/threads/new-version-may-22nd-5-22.615959/).
The Sakoku part of the UA isn't attractive with the addition of culture on trade routes either. Japan usually takes time to get a cultural or scientific advantage, so it actually wants to receive trade routes early on, rather than block them, especially when you have only 1 route. The Sakoku part may need a revision or adaptation.
And the UA still encourages warfare even before Japan has access to its unique promotion. Maybe the Dojo's promotion should be back to the UA, as it is in the vanilla? Japan originally had a combat advantage already at turn 1, the promotion works really well with Authority's policies and the original reason for moving it to the Dojo was because the former "GWAM on GG/GA + Sakoku" UA wording was too long. Swapping the Dojo promotion with the UA "yields on leveling" may end netting more early yields from Authority's policies, at least for the player, due to its better timing.
The virtues may also be more interesting at Ancient Era, when you still have very few units and need to maximize any unique benefits and combinations they may provide. The way you try to maximize a Courage + Righteousness combination of early warriors would be different from a Self Control + Benevolence or Honor + Loyalty, for instance.
Overall, I'd consider the following:
- Swapping the Dojo's promotion with the UA's "yields on leveling"
- Increase the Dojo's free XP to make the lategame yields less reliant on Orders and Branderburg Gate
- revision Sakoku in light of the culture on trade routes