I think it would be attractive to make it six barrels for the main artillery. Only four is very little for properly ranging in on targets(one of the many failures of the Outrageous class).

snip(one of the many failures of the Outrageous class).

I'm not even sure that any of the 13.5in turrets or guns ever were retained once the last of that series of dreadnoughts and Tiger were scrapped in the early 1930s.

Nice designs Jabba, but here are some points
The CA1 design should have bridge wings to the bridge. As it is now they are lacking. I believe the searchlight on the mast is not customarily carried by RN ships. Also I don't think you'll have torpedo tubes on ships of this kind (at least not in the 1920's or 1930's)
On the CA1 design the 4" guns should be 2 on each side with no super firing mountings above the main armament. Also, the bows on CA1 is too long, and I suggest moving everything forward and work in a hangar with athwart-ship catapult (like on the HMS Belfast)
The CA2 design although looks odd (by virtue of it being single ended, like HMS Rodney) the AA armament of 4" is badly placed with no guns for forward AA firing arcs. I also think that placing the quadruple .5" guns on the platform of the funnel is bad, because of ammunition supply. Again the bows of the ship is too long and empty and you can add a hangar and catapult if you move everything forward.
Note that I'm not suggesting to shorten the ships as it will hamper their hydrodynamics.

How many gerbils power that?

As a replacement for the KGV series I see these as failures. By this time all of the major European powers were still building capital ships (even Germany) and you can't forget the mindset of the Admiralty - the Royal Navy was the most powerful on earth (in their minds, at the very least) - so therefore required capital ships. The fact they stuck like Gentlemen to the London Treaty etc. meant those ships were less successful then they might have been, but in hindsight we can say they were good enough. Pit one of these against Bismarck in 1941 and its curtains, even against Graf Spee in 1939 the odds might be closer than we think due to the small number of barrels, Exeter was wrecked but the danger of three targets split her fire. Of course had Harwood one of these for support a long-range duel would have favoured the bigger gun.
Generally I see the Panzerschiff as a largely bogus concept when its wheeled out in such AU scenarios. We musn't forget the Weimar regime had no other choice, they were constrained to displacements and guns far below the other powers. That they developed such a long-ranged raiding ship rather than a mundane Scandnavian-style coastal defence ship was perhaps a bit of foresight and certainly radical thinking. Even so, they have had more historical impact than possibly warranted from their careers and in my view any foreign attempts to build a similar type would be widely different in concept and execution. Even so it's good to see some RN AU ships trying to push the boundaries.

Nice drawings, but a rather dubious basis for an AU...