You can balance the 3-hits by allowing attacking, not defending subs hits against the Dreadnaughts to count double.
As always, the defender should pick where to allocate hits.
Realistically, the range of their guns scared away the Allied surface ships.
Superior US intel often prevented these Japanese monsters from finding their prey, so it would be safe to say that they were not effectively used in attack. Superior USN air power allowed us to pick the battles where we finally sunk them.
The Japs developed pellet spraying shot for their big guns, but I think the regular hull-mounted AA’s were better against air. I think they also had other specialized shore bombardment shells, but by then, they were defending rather than conducting beach landings.