Sometimes, designs are on a "sweet spot": the Ger/CA/1906 design study

The Ger/CA/1906 is sort of an expansive armoured cruiser or small battlecruiser. I have a small pencil sketch and a set of specifications, including weights. The ship has 6-12in/50 in triple turrets at the ends and 8-6in QF guns in casemates below the forecastle level, amidships. The armour basis is 6in, with a 3in deck. The speed is 25 knots. The design does not depend on lightweight machinery, but uses 1906 technology. This is the Springsharp report:

Ger/CA/1906, Germany Armoured Cruiser laid down 1906

Displacement:
    15,175 t light; 15,850 t standard; 18,250 t normal; 20,170 t full load

Dimensions: Length overall / water x beam x draught
    550.00 ft / 550.00 ft x 80.00 ft x 25.00 ft (normal load)
    167.64 m / 167.64 m x 24.38 m  x 7.62 m

Armament:
      6 - 12.00" / 305 mm guns (2x3 guns), 864.00lbs / 391.90kg shells, 1906 Model
      Breech loading guns in turrets (on barbettes)
      on centreline ends, evenly spread
      8 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1906 Model
      Quick firing guns in casemate mounts
      on side, all amidships, all raised mounts - superfiring
    Weight of broadside 6,048 lbs / 2,743 kg
    Shells per gun, main battery: 90

Armour:
   - Belts:        Width (max)    Length (avg)        Height (avg)
    Main:    6.00" / 152 mm    375.00 ft / 114.30 m    16.00 ft / 4.88 m
    Ends:    Unarmoured
      Main Belt covers 105 % of normal length
      Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
        1.00" / 25 mm    375.00 ft / 114.30 m    25.00 ft / 7.62 m

   - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    6.00" / 152 mm    4.00" / 102 mm        6.00" / 152 mm
    2nd:    3.00" / 76 mm    3.00" / 76 mm        3.00" / 76 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 6.00" / 152 mm

Machinery:
    Oil fired boilers, steam turbines,
    Direct drive, 4 shafts, 51,011 shp / 38,054 Kw = 25.00 kts
    Range 6,300nm at 15.00 kts
    Bunker at max displacement = 4,320 tons

Complement:
    784 - 1,020

Cost:
    £1.630 million / $6.520 million

Distribution of weights at normal displacement:
    Armament: 756 tons, 4.1 %
    Armour: 4,444 tons, 24.4 %
       - Belts: 1,545 tons, 8.5 %
       - Torpedo bulkhead: 347 tons, 1.9 %
       - Armament: 708 tons, 3.9 %
       - Armour Deck: 1,754 tons, 9.6 %
       - Conning Tower: 90 tons, 0.5 %
    Machinery: 3,312 tons, 18.2 %
    Hull, fittings & equipment: 6,663 tons, 36.5 %
    Fuel, ammunition & stores: 3,075 tons, 16.8 %
    Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      24,314 lbs / 11,029 Kg = 28.1 x 12.0 " / 305 mm shells or 3.3 torpedoes
    Stability (Unstable if below 1.00): 1.27
    Metacentric height 5.5 ft / 1.7 m
    Roll period: 14.3 seconds
    Steadiness    - As gun platform (Average = 50 %): 76 %
            - Recoil effect (Restricted arc if above 1.00): 0.59
    Seaboat quality  (Average = 1.00): 1.51

Hull form characteristics:
    Hull has rise forward of midbreak
    Block coefficient: 0.581
    Length to Beam Ratio: 6.88 : 1
    'Natural speed' for length: 23.45 kts
    Power going to wave formation at top speed: 53 %
    Trim (Max stability = 0, Max steadiness = 100): 50
    Bow angle (Positive = bow angles forward): -2.00 degrees
    Stern overhang: -2.00 ft / -0.61 m
    Freeboard (% = measuring location as a percentage of overall length):
       - Stem:        28.00 ft / 8.53 m
       - Forecastle (20 %):    25.00 ft / 7.62 m
       - Mid (68 %):        25.00 ft / 7.62 m (17.00 ft / 5.18 m aft of break)
       - Quarterdeck (15 %):    17.00 ft / 5.18 m
       - Stern:        17.00 ft / 5.18 m
       - Average freeboard:    22.68 ft / 6.91 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 120.1 %
        - Above water (accommodation/working, high = better): 175.9 %
    Waterplane Area: 31,604 Square feet or 2,936 Square metres
    Displacement factor (Displacement / loading): 107 %
    Structure weight / hull surface area: 142 lbs/sq ft or 691 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.92
        - Longitudinal: 1.99
        - Overall: 1.00
    Hull space for machinery, storage, compartmentation is cramped
    Room for accommodation and workspaces is excellent
    Ship has slow, easy roll, a good, steady gun platform
    Excellent seaboat, comfortable, can fire her guns in the heaviest weather