So the Heimdallr became the protoype for the battlecruiser of the Unified Norse Navy. Ideas were tested and some discarded from future designs. The most prominent is that the following ships had all turrets mounted on the centerline like the battleships. The Tyr, the first dreadnought was originally to have one front, one aft and four turrets amidships ala Nassau. But earlier cruiser designs suffered som drawbacks becasue of that layout and the Heimdallr was too far into construction to redesign. The navy was barely able to convert the Tyr to an all centerline layout. The next class of battlecruiser, the Kvasir (pronounced Vasir) had five turrets, all amidships. Three aft, one front and one amidships. The three turrets aft was a legacy from the Tyr, of which both the Heimdallr and Kvasir is closely related to. The hull and superstructure of the Heimdallr and Kvasir is much alike, the casemates are one deck up and the ship is the first to have the classic Norse and German conning tower. The ship retains the 12 inch guns of the Tyr and Heimdallr on an enlargened hull almost as long as the Freyr class.
The Loki class was the last battlecruiser built before the war. The Loki was the contemporary Viking ship of the Freyr class battleship and the two shared many design features. The Loki distinguished it self from the others for it`s layout: one forward 14" turret, two superfiring turrets amidship and two superfiring aft. The Loki is not that much bigger than the Kvasir but weights much more due to much thicker armor.
One battlecruiser class is to be built during the war and two new designs arise based on wartime experience.
The battlecruiser built during the war is to have eight or ten 15 inch guns, the same as the Sleipner class. The other two designs will have 16 inch guns from the Ægir class.