I think the Type 3 shell for Yamato's main gun was suggested before (naturally since it's a historical round).

I don't see the harm myself, seeing it's largely harmless due to its long reload time and that the user reduces his potential anti-ship damage output by loading them. It is one of the historically accurate things that NF can afford to have, since the round would be quite useless in the game as it was in real life.

I would prefer to see grapeshot before this gets implemented.

It would be interesting, but really useless. The Shrapnel/Incindiery Rounds exploded into an extremely narrow shotgun effect rather than a spherical explosivion.

Smaller guns like the 16inch, 8inch and 5inch IJN guns could also mount the Beehive ammunition, but had the same narrow blast zone.

It would be sad really to see large guns with so-so angles firing AA ammo and long-reloads.

Oh and if the Japanese fleets gets the Sanshiki Beehive Ammunition, than the American Ships get the Proximity ammunition. With that American Ships would compete heavily with the Kreigsmarine ships as the Anti-air masters.