To me, Graf is fine where she is, or she could be replaced with Bisko instead. Bisko is the one that should be replaced by Roma, and maybe Gangut with Warspite (or even Kongou!) =3
I suddenly want to to read an Akatsuki and Bismarck fanfiction. In fact I suddenly started 'shipping' them.
Just search for them both on Danbooru. There's plenty of artwork of the two of them together. They are often called "small Bismarck" and "big Akatsuki" because of their similar personalities in fanon. It's pretty obvious that Bismarck would be one of those older shipgirls that Akatsuki looks up to the most.
Gangut: Bismark its only been two events but it feels like years, and you...um, how are...wanna say Ferdi? Birmark whats this girl's name? Bismarck: Hrrrrm Gangut: Oh better watch out for Hrrrrm
Anyone! Old man (Admiral)? Bring the Sixth DesDiv over here!What's starting?World War 3?
Commando reference