The Ger/CB/1912 design works well

I followed the combined Red and Blue Book information about the Ger/CB/1912 design and attempted to use those specifications as closely as I could. I followed the very limited armoured citadel length (400ft on an 820ft vessel). I had envisioned a 37,000 ton normal displacement. The Springsharp report gave me 37,600 tons, which considering how the ship was designed, was quite good. This is a ship were the main armament of 6-15in guns is all forward with 8-6in QF guns in shields. This is the photo, which gives a pretty good idea of what the ships looked like:

This is the Springsharp report:

Ger/CB/1912, Germany Battlecruiser laid down 1912 (Engine 1927)

Displacement:
 34,287 t light; 35,595 t standard; 37,600 t normal; 39,204 t full load

Dimensions: Length overall / water x beam x draught
 824.00 ft / 820.00 ft x 105.00 ft x 30.00 ft (normal load)
 251.16 m / 249.94 m x 32.00 m  x 9.14 m

Armament:
      6 - 15.00" / 381 mm guns (2x3 guns), 1,687.50lbs / 765.44kg shells, 1912 Model
   Breech loading guns in turrets (on barbettes)
   on centreline, all forward, 1 raised mount - superfiring
      8 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1912 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships, 2 raised mounts - superfiring
 Weight of broadside 10,989 lbs / 4,985 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 7.00" / 178 mm 400.00 ft / 121.92 m 9.00 ft / 2.74 m
 Ends: Unarmoured
 Upper: 5.00" / 127 mm 400.00 ft / 121.92 m 10.00 ft / 3.05 m
   Main Belt covers 75 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  2.00" / 51 mm 400.00 ft / 121.92 m 30.00 ft / 9.14 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 10.0" / 254 mm 6.00" / 152 mm  10.0" / 254 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 6.00" / 152 mm, Conning tower: 10.00" / 254 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 164,478 shp / 122,701 Kw = 31.50 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 3,608 tons

Complement:
 1,349 - 1,755

Cost:
 £3.081 million / $12.323 million

Distribution of weights at normal displacement:
 Armament: 1,374 tons, 3.7 %
 Armour: 11,622 tons, 30.9 %
    - Belts: 2,043 tons, 5.4 %
    - Torpedo bulkhead: 888 tons, 2.4 %
    - Armament: 2,026 tons, 5.4 %
    - Armour Deck: 6,423 tons, 17.1 %
    - Conning Tower: 242 tons, 0.6 %
 Machinery: 5,192 tons, 13.8 %
 Hull, fittings & equipment: 16,099 tons, 42.8 %
 Fuel, ammunition & stores: 3,313 tons, 8.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   60,414 lbs / 27,403 Kg = 35.8 x 15.0 " / 381 mm shells or 8.6 torpedoes
 Stability (Unstable if below 1.00): 1.15
 Metacentric height 6.9 ft / 2.1 m
 Roll period: 16.7 seconds
 Steadiness - As gun platform (Average = 50 %): 70 %
   - Recoil effect (Restricted arc if above 1.00): 0.56
 Seaboat quality  (Average = 1.00): 1.41

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.509
 Length to Beam Ratio: 7.81 : 1
 'Natural speed' for length: 28.64 kts
 Power going to wave formation at top speed: 51 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: 4.00 ft / 1.22 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  38.00 ft / 11.58 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (60 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 27.44 ft / 8.36 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 89.7 %
  - Above water (accommodation/working, high = better): 220.0 %
 Waterplane Area: 57,866 Square feet or 5,376 Square metres
 Displacement factor (Displacement / loading): 114 %
 Structure weight / hull surface area: 191 lbs/sq ft or 934 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.55
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Good seaboat, rides out heavy weather easily