A large German heavy cruiser: the Ger/CA/1937

This is my design for an outsized German heavy cruiser with 9-9.4in BLR, 12-4.1in AA, and 32-37mm AA guns. The belt is 5in and the deck is 2in. The speed is 33 knots and the range is 12,000nm at 15 knots. I had an idea that this would be a commerce raider. This is the Springsharp report:

Ger/CA/1937, Germany Heavy Cruiser laid down 1937

Displacement:
 17,022 t light; 17,813 t standard; 20,050 t normal; 21,839 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (757.84 ft / 745.00 ft) x 82.00 ft x (21.00 / 22.47 ft)
 (230.99 m / 227.08 m) x 24.99 m  x (6.40 / 6.85 m)

Armament:
      9 - 9.40" / 239 mm 55.0 cal guns - 450.00lbs / 204.12kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1937 Model
   3 x Triple mounts on centreline ends, majority forward
  1 raised mount - superfiring
      16 - 4.10" / 104 mm 55.0 cal guns - 36.00lbs / 16.33kg shells, 150 per gun
   Anti-air guns in deck and hoist mounts, 1937 Model
   8 x Twin mounts on sides, forward deck aft
  8 raised mounts
      32 - 1.46" / 37.0 mm 65.0 cal guns - 1.71lbs / 0.78kg shells, 150 per gun
   Anti-air guns in deck mounts, 1937 Model
   16 x Twin mounts on sides amidships
  16 raised mounts
      Weight of broadside 4,681 lbs / 2,123 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 5.00" / 127 mm 490.00 ft / 149.35 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 101 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 490.00 ft / 149.35 m 21.00 ft / 6.40 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: 1.00" / 25 mm 1.00" / 25 mm  1.00" / 25 mm

   - Armoured deck - multiple decks: 2.00" / 51 mm For and Aft decks

   - Conning towers: Forward 6.00" / 152 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 139,837 shp / 104,318 Kw = 33.00 kts
 Range 12,000nm at 15.00 kts
 Bunker at max displacement = 4,025 tons

Complement:
 842 - 1,095

Cost:
 £9.137 million / $36.549 million

Distribution of weights at normal displacement:
 Armament: 1,276 tons, 6.4 %
 Armour: 3,713 tons, 18.5 %
    - Belts: 1,219 tons, 6.1 %
    - Torpedo bulkhead: 381 tons, 1.9 %
    - Armament: 797 tons, 4.0 %
    - Armour Deck: 1,220 tons, 6.1 %
    - Conning Tower: 95 tons, 0.5 %
 Machinery: 3,876 tons, 19.3 %
 Hull, fittings & equipment: 8,158 tons, 40.7 %
 Fuel, ammunition & stores: 3,027 tons, 15.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   30,442 lbs / 13,808 Kg = 73.3 x 9.4 " / 239 mm shells or 3.9 torpedoes
 Stability (Unstable if below 1.00): 1.20
 Metacentric height 5.2 ft / 1.6 m
 Roll period: 15.1 seconds
 Steadiness - As gun platform (Average = 50 %): 56 %
   - Recoil effect (Restricted arc if above 1.00): 0.46
 Seaboat quality  (Average = 1.00): 1.13

Hull form characteristics:
 Hull has a flush deck,
   an extended bulbous bow and a cruiser stern
 Block coefficient (normal/deep): 0.547 / 0.557
 Length to Beam Ratio: 9.09 : 1
 'Natural speed' for length: 27.29 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 15.00 degrees
 Stern overhang: 4.00 ft / 1.22 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 20.00 %,  33.00 ft / 10.06 m,  26.00 ft / 7.92 m
    - Forward deck: 30.00 %,  26.00 ft / 7.92 m,  23.00 ft / 7.01 m
    - Aft deck: 30.00 %,  23.00 ft / 7.01 m,  23.00 ft / 7.01 m
    - Quarter deck: 20.00 %,  23.00 ft / 7.01 m,  24.00 ft / 7.32 m
    - Average freeboard:  24.71 ft / 7.53 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 115.8 %
  - Above water (accommodation/working, high = better): 228.4 %
 Waterplane Area: 42,514 Square feet or 3,950 Square metres
 Displacement factor (Displacement / loading): 121 %
 Structure weight / hull surface area: 141 lbs/sq ft or 690 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.16
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent