I will be convinced of the value of the UK battleship (or the US dd/sub, for that matter) when I see it used effectively against me. (I’m still not convinced that Allies have reasonable win chances at all.) The only thing I see the J2 giving up in terms of kills is the US fighter. The suicide-the-BB thing seems to me even less effective than it getting a 2/3rds chance to destroy a cruiser. Suiciding ANZAC fleet doesn’t sound like a great idea either… my IJN defensive fleet is always parked at a harbor, so whatever damage they do gets absorbed by bb/ac and repaired (with air replaced onto the carriers as needed) before the US gets to follow up. So between them both suicide attacks will generally need to add up to 5 hits or more before even a sub or destroyer gets removed from the board, and that would require a big sacrifice of material.
As far as the cruiser goes, I know that as Japan I use that thing every single turn to do something important. It’s not always bombarding, but it does get a lot of shots and it does project a lot of threat. On the topic of bombarding, repeated bombard shots are a great way to whittle down a large stack against an opponent with low income when you can’t take on the whole stack at once. Japan has several situations where this happens - against India, against the Russians if they come, and later on when assaulting Australia for the win. It’s another option I’d rather not forego if I don’t have to, and I don’t perceive that necessity.
Typical scenario: India with 25ish units on it but only 6 income, throw 2inf 2art at it with 4 amphib shots, on average you’ll score 3 2/3rds hits - just under an even return - with a decent chance to get more, and you don’t risk any more than four units for that roll of the dice. Rolls of the dice that could go very bad for the opponent where it doesn’t really hurt you if it goes bad for you and the odds are reasonable to get the good outcome, those are pure money in a game like this. It’s basically a small strafe with a capped risk, get completely diced and your cost is 14 tops, and you don’t need make stack in Burma to try. Take those chances every time you see them, I say - the bombards give you more of those chances.
As an aside, this conversation gave me an idea I’m going to try. My expeditionary fleet with Japan is usually bb/cruiser/2ac and escorts. I’m going to try swapping out the 2nd AC for the other bb/cruiser pair to have four amphibious shots in the one group and see if that magnifies the threat even further. Perhaps there is not a lot of fear of two bombard shots from a fleet, but four shots might be a different story.